U.S. patent application number 15/400084 was filed with the patent office on 2017-04-27 for photoelectric conversion element, dye-sensitized solar cell, metal complex dye, dye solution, and terpyridine compound or esterified product thereof.
This patent application is currently assigned to FUJIFILM Corporation. The applicant listed for this patent is FUJIFILM Corporation. Invention is credited to Katsumi KOBAYASHI, Kousuke WATANABE, Tomoaki YOSHIOKA.
Application Number | 20170117100 15/400084 |
Document ID | / |
Family ID | 55064147 |
Filed Date | 2017-04-27 |
United States Patent
Application |
20170117100 |
Kind Code |
A1 |
YOSHIOKA; Tomoaki ; et
al. |
April 27, 2017 |
PHOTOELECTRIC CONVERSION ELEMENT, DYE-SENSITIZED SOLAR CELL, METAL
COMPLEX DYE, DYE SOLUTION, AND TERPYRIDINE COMPOUND OR ESTERIFIED
PRODUCT THEREOF
Abstract
A photoelectric conversion element including an electrically
conductive support, a photoconductor layer including an
electrolyte, a charge transfer layer including an electrolyte, and
a counter electrode, in which the photoconductor layer has
semiconductor fine particles carrying a metal complex dye
represented by Formula (I). Also disclosed is a dye-sensitized
solar cell; a metal complex dye; a dye solution; and a terpyridine
compound or an esterified product thereof:
M(LA)(LD).sub.p(LX).sub.q.(CI).sub.z Formula (I) wherein M
represents a metal ion, LD represents a bidentate or tridentate
ligand, p represents 0 or 1, LX represents a monodentate ligand, q
represents 0, 1, or 3, CI represents a counterion, z represents an
integer of 0 to 3, and LA represents a tridentate ligand
represented by Formula (LA-1) as defined herein ##STR00001##
Inventors: |
YOSHIOKA; Tomoaki;
(Ashigarakami-gun, JP) ; WATANABE; Kousuke;
(Ashigarakami-gun, JP) ; KOBAYASHI; Katsumi;
(Ashigarakami-gun, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FUJIFILM Corporation |
Tokyo |
|
JP |
|
|
Assignee: |
FUJIFILM Corporation
Tokyo
JP
|
Family ID: |
55064147 |
Appl. No.: |
15/400084 |
Filed: |
January 6, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/JP2015/068976 |
Jul 1, 2015 |
|
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15400084 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01G 9/2059 20130101;
H01G 9/2009 20130101; C09B 57/10 20130101; H01L 51/42 20130101;
H01L 51/0086 20130101; C07D 409/14 20130101; H01G 9/20 20130101;
Y02E 10/542 20130101 |
International
Class: |
H01G 9/20 20060101
H01G009/20; H01L 51/00 20060101 H01L051/00; C09B 57/10 20060101
C09B057/10; C07D 409/14 20060101 C07D409/14 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 7, 2014 |
JP |
2014-140078 |
Jun 4, 2015 |
JP |
2015-113836 |
Claims
1. A photoelectric conversion element comprising: an electrically
conductive support; a photoconductor layer including an
electrolyte; a charge transfer layer including an electrolyte; and
a counter electrode, wherein the photoconductor layer has
semiconductor fine particles carrying a metal complex dye
represented by the following Formula (I),
M(LA)(LD).sub.p(LX).sub.q.(CI).sub.z Formula (I) in the formula, M
represents a metal ion, LA represents a tridentate ligand
represented by the following Formula (LA-1), LD represents a
bidentate or tridentate ligand, and p represents 0 or 1, LX
represents a monodentate ligand, and when p is 0, q represents 3;
when p is 1 and LD is a tridentate ligand, q represents 0; and when
p is 1 and LD is a bidentate ligand, q represents 1, and CI
represents a counterion necessary for neutralizing the charge of
the metal complex dye, and z represents an integer of 0 to 3;
##STR00402## in the formula, Za and Zb each independently represent
a non-metal atomic group necessary for forming a 5- or 6-membered
ring, in which at least one of rings formed by Za and Zb,
respectively, has an acidic group, L.sup.W's each independently
represent a nitrogen atom or CR.sup.W, and R.sup.W represents a
hydrogen atom or a substituent, Het.sup.1 represents a
heteroarylene group including a thiophene ring bonded to a hetero
ring including L.sup.W, Ar.sup.1 represents an arylene group or a
heteroarylene group, and m represents an integer of 0 to 5, and
R.sup.1 and R.sup.2 each independently represent an alkyl group, an
aryl group, or a heteroaryl group.
2. The photoelectric conversion element according to claim 1,
wherein the ring formed by Za is at least one selected from the
group consisting of a pyridine ring, a pyrimidine ring, a pyrazine
ring, a pyridazine ring, a triazine ring, a tetrazine ring, a
quinoline ring, an isoquinoline ring, an imidazole ring, a pyrazole
ring, a triazole ring, a thiazole ring, an oxazole ring, a
benzimidazole ring, a benzotriazole ring, a benzoxazole ring, and a
benzothiazole ring, the ring formed by Zb is at least one selected
from the group consisting of a pyridine ring, a pyrimidine ring, a
pyrazine ring, a pyridazine ring, a triazine ring, a tetrazine
ring, a quinoline ring, an isoquinoline ring, an imidazole ring, a
triazole ring, a thiazole ring, an oxazole ring, a benzimidazole
ring, a benzotriazole ring, a benzoxazole ring, and a benzothiazole
ring, and the hetero ring including L.sup.W is at least one
selected from the group consisting of a pyridine ring, a pyrimidine
ring, a pyridazine ring, a triazine ring, a tetrazine ring, a
quinoline ring, and an isoquinoline ring.
3. The photoelectric conversion element according to claim 1,
wherein M is Ru.sup.2+ or Os.sup.2+.
4. The photoelectric conversion element according to claim 1,
wherein LA is represented by the following Formula (LA-2),
##STR00403## in the formula, Het.sup.1, Ar.sup.1, m, R.sup.1, and
R.sup.2 have the same definitions as Het.sup.1, Ar.sup.1, m,
R.sup.1, and R.sup.2, respectively, in Formula (LA-1), and Anc1 and
Anc2 each independently represent an acidic group.
5. The photoelectric conversion element according to claim 1,
wherein R.sup.1 and R.sup.2 are all aryl groups or heteroaryl
groups.
6. The photoelectric conversion element according to claim 1,
wherein Het.sup.1 is a thiophene ring group represented by any one
of the following Formulae (AR-1) to (AR-3), ##STR00404## in the
formulae, R.sup.L1 to R.sup.L6 each independently represent a
hydrogen atom or a substituent, and R.sup.L1 and R.sup.L2 may be
linked to each other to form a ring, and * represents a binding
position to the hetero ring including L.sup.W, and ** represents a
binding position to Ar.sup.1 or the N atom in Formula (LA-1).
7. The photoelectric conversion element according to claim 1,
wherein LA is represented by the following Formula (LA-3),
##STR00405## in the formula, Y.sup.1 represents an oxygen atom, a
sulfur atom, or --CR.sup.L21.dbd.CR.sup.L22--, R.sup.L7 to
R.sup.L22 each independently represent a hydrogen atom or a
substituent, and adjacent two members of R.sup.L7 to R.sup.L22 may
be linked to each other to form a ring, Anc1 and Anc2 each
independently represent an acidic group, and n represents 0 or
1.
8. The photoelectric conversion element according to claim 1,
wherein the acidic group is a carboxyl group or a salt thereof.
9. The photoelectric conversion element according to claim 1,
wherein LD is a bidentate ligand represented by any one of the
following Formulae (2L-1) to (2L-4), ##STR00406## in the formulae,
the ring D.sup.2L represents an aromatic ring, A.sup.111 to
A.sup.141 each independently represent an anion of a nitrogen atom
or an anion of a carbon atom, R.sup.111 to R.sup.143 each
independently represent a hydrogen atom or a substituent not having
an acidic group, and * represents a coordinating position to the
metal ion M.
10. The photoelectric conversion element according to claim 1,
wherein LD is a tridentate ligand represented by any one of the
following Formulae (3L-1) to (3L-4), ##STR00407## in the formulae,
the ring D.sup.2L represents an aromatic ring, A.sup.211 to
A.sup.242 each independently represent a nitrogen atom or a carbon
atom, in which at least one of each of A.sup.211 and A.sup.212,
A.sup.221 and A.sup.222, A.sup.231 and A.sup.232, and A.sup.241 and
A.sup.242 is an anion, R.sup.211 to R.sup.241 each independently
represent a hydrogen atom or a substituent not having an acidic
group, and * represents a coordinating position to the metal ion
M.
11. A dye-sensitized solar cell comprising the photoelectric
conversion element according to claim 1.
12. A metal complex dye represented by the following Formula (I),
M(LA)(LD).sub.p(LX).sub.q.(CI).sub.z Formula (I) in the formula, M
represents a metal ion, LA represents a tridentate ligand
represented by the following Formula (LA-1), LD represents a
bidentate or tridentate ligand, and p represents 0 or 1, LX
represents a monodentate ligand, and when p is 0, q represents 3;
when p is 1 and LD is a tridentate ligand, q represents 0; and when
p is 1 and LD is a bidentate ligand, q represents 1, and CI
represents a counterion necessary for neutralizing the charge of
the metal complex dye, and z represents an integer of 0 to 3;
##STR00408## in the formula, Za and Zb each independently represent
a non-metal atomic group necessary for forming a 5- or 6-membered
ring, in which at least one of rings formed by Za and Zb,
respectively, has an acidic group, L.sup.W's each independently
represent a nitrogen atom or CR.sup.W and R.sup.W represents a
hydrogen atom or a substituent, Het.sup.1 represents a
heteroarylene group including a thiophene ring bonded to a hetero
ring including L.sup.W, Ar.sup.1 represents an arylene group or a
heteroarylene group, and m represents an integer of 0 to 5, and
R.sup.1 and R.sup.2 each independently represent an alkyl group, an
aryl group, or a heteroaryl group.
13. A dye solution comprising the metal complex dye according to
claim 12 and a solvent.
14. A terpyridine compound represented by the following Formula
(LA-2), or an esterified product thereof, ##STR00409## in the
formula, Het.sup.1 represents a heteroarylene group including a
thiophene ring bonded to a pyridine ring, Ar.sup.1 represents an
arylene group or a heteroarylene group, and m represents an integer
of 0 to 5, R.sup.1 and R.sup.2 each independently represent an
alkyl group, an aryl group, or a heteroaryl group, and Anc1 and
Anc2 each independently represent an acidic group.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation of PCT International
Application No. PCT/JP2015/068976 filed on Jul. 1, 2015, which
claims priorities under 35 U.S.C. .sctn.119 (a) to Japanese Patent
Application No. JP2014-140078, filed on Jul. 7, 2014, and
JP2015-113836, filed on Jun. 4, 2015. Each of the above
applications is hereby expressly incorporated by reference, in its
entirety, into the present application.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a photoelectric conversion
element, a dye-sensitized solar cell, a metal complex dye, a dye
solution, and a terpyridine compound or an esterified product
thereof.
[0004] 2. Description of the Related Art
[0005] Photoelectric conversion elements are used in various
photosensors, copying machines, photoelectrochemical cells such as
solar cells, and the like. These photoelectric conversion elements
have adopted various systems to be put into use, such as systems
utilizing metals, systems utilizing semiconductors, systems
utilizing organic pigments or dyes, or combinations of these
elements. In particular, solar cells utilizing inexhaustible solar
energy do not necessitate fuels, and full-fledged practicalization
of solar cells as an inexhaustible clean energy is being highly
expected. Above all, research and development of silicon-based
solar cells has long been in progress, and many countries also
support policy-wise considerations, and thus dissemination of
silicon-based solar cells is still in progress. However, silicon is
an inorganic material, and thus, naturally has limitations in terms
of improvement of throughput, cost, and the like.
[0006] Therefore, research is being vigorously carried out on
photoelectrochemical cells (also referred to as dye-sensitized
solar cells), using metal complex dyes. In particular, the research
was fueled by the results of research conducted by Graetzel et al.
of Ecole Polytechnique Federale de Lausanne in Switzerland. They
adopted a structure in which a dye formed from a ruthenium complex
was fixed on the surface of a porous titanium oxide film, and
realized photoelectric conversion efficiency that is equivalent to
that of amorphous silicon. Thus, dye-sensitized solar cells that
can be produced even without use of expensive vacuum devices have
instantly drawn the attention of researchers all over the
world.
[0007] Hitherto, dyes called N3, N719, N749 (also referred to as
Black Dye), Z907, and J2, and the like have generally been
developed as metal complex dyes for use in dye-sensitized solar
cells. However, all of the photoelectric conversion elements and
dye-sensitized solar cells using these dyes are not sufficient in
terms of photoelectric conversion efficiency and durability (heat
stability).
[0008] Therefore, development of metal complex dyes capable of
improving the photoelectric conversion efficiency or the durability
of photoelectric conversion elements and dye-sensitized solar cells
is in progress.
[0009] For example, JP2012-36237A describes a metal complex dye
having a terpyridine ligand with a terminal pyridine ring to which
a thiophene ring group substituted with an alkyl group having 15
carbon atoms is bonded. It also describes that a
photoelectrochemical cell using the metal complex dye has high
photoelectric conversion efficiency and excellent durability.
[0010] JP2013-67773A describes a metal complex dye having a
terpyridine ligand in which a benzene ring group or thiophene ring
group including an amino group is bonded at the 3-position with
respect to the ring-constituting nitrogen atom coordinating to a
metal ion of a terminal pyridine ring, and three monodentate
ligands. It also describes that a photoelectrochemical cell using
the metal complex dye accomplishes high photoelectric conversion
efficiency and has excellent durability.
[0011] JP2013-229285A describes a metal complex dye having a
terpyridine ligand in which a thiophene ring group substituted with
an alkyl group is bonded at the 3-position with respect to the
ring-constituting nitrogen atom coordinating to a metal ion of a
terminal pyridine ring, and a doner ligand having a cyclic group
substituted with a specific substituent. It also describes that a
photoelectrochemical cell using the metal complex dye accomplishes
both of reduction in performance irregularity and improvement of
photoelectric conversion efficiency and durability.
[0012] US2012/0247561A describes a tridentate ligand in which an
aryl ring group including an amino group is bonded at the
3-position with respect to the ring-constituting nitrogen atom
coordinating to a metal ion of an .alpha.-pyridine ring, and a
metal complex having this ligand and three thioisocyanate
anions.
SUMMARY OF THE INVENTION
[0013] However, in recent years, studies and development of
photoelectric conversion elements and dye-sensitized solar cells
have been actively conducted, and thus, increasingly higher
performance thereof is required. There is a demand for, in
particular, further enhancement and improvements in their
photoelectric conversion efficiency and durability.
[0014] In photoelectric conversion elements and dye-sensitized
solar cells, a layer (also referred to as a semiconductor layer)
which is formed of semiconductor fine particles and carries a metal
complex dye is usually formed into a layer with a thickness of 10
to several hundred .mu.m. For such photoelectric conversion
elements and dye-sensitized solar cells, reduction in thickness
(size) and weight has been required. However, the photoelectric
conversion efficiency varies depending on the film thickness of a
semiconductor layer, and tends to decrease as the film thickness
becomes smaller. Accordingly, excellent photoelectric conversion
efficiency is required to be exhibited even in a case where the
film thickness of the semiconductor layer is small.
[0015] The present invention has an object to provide a
photoelectric conversion element and a dye-sensitized solar cell,
each of which is less affected by the film thickness of a
semiconductor layer, exhibits excellent photoelectric conversion
efficiency, particularly even when the film thickness is small, and
has high durability; and a metal complex dye, a dye solution, and a
terpyridine compound or an esterified product thereof, each of
which is used in the photoelectric conversion element and the
dye-sensitized solar cell.
[0016] The present inventors have conducted various investigations
on metal complex dyes for use in photoelectric conversion elements
and dye-sensitized solar cells, and as a result, they have found
that it is important to introduce a specific amino group-containing
heteroarylene group at the ring-constituting atom at the 4-position
with respect to a ring-constituting nitrogen atom coordinating to a
metal ion in a terminal nitrogen-containing ring in a tridentate
ligand having a nitrogen-containing ring bonded thereto, for
further improvement of photoelectric conversion efficiency and
durability as well as realization of high photoelectric conversion
efficiency even when a semiconductor layer is a thin film in the
photoelectric conversion elements and the dye-sensitized solar
cells. Based on these findings, the present invention has been
completed.
[0017] That is, the objects of the present invention have been
achieved by the following means.
[0018] <1> A photoelectric conversion element comprising:
[0019] an electrically conductive support;
[0020] a photoconductor layer including an electrolyte;
[0021] a charge transfer layer including an electrolyte; and
[0022] a counter electrode,
[0023] in which the photoconductor layer has semiconductor fine
particles carrying a metal complex dye represented by the following
Formula (I),
M(LA)(LD)p(LX)q.(CI).sub.z Formula (I)
[0024] in the formula,
[0025] M represents a metal ion,
[0026] LA represents a tridentate ligand represented by the
following Formula (LA-1),
[0027] LD represents a bidentate or tridentate ligand, and p
represents 0 or 1,
[0028] LX represents a monodentate ligand, and when p is 0, q
represents 3; when p is 1 and LD is a tridentate ligand, q
represents 0; and when p is 1 and LD is a bidentate ligand, q
represents 1, and
[0029] CI represents a counterion necessary for neutralizing the
charge of the metal complex dye, and z represents an integer of 0
to 3; and
##STR00002##
[0030] in the formula,
[0031] Za and Zb each independently represent a non-metal atomic
group necessary for forming a 5- or 6-membered ring, in which at
least one of rings formed by Za and Zb, respectively, has an acidic
group, L.sup.W's each independently represent a nitrogen atom or
CR.sup.W, and R.sup.W represents a hydrogen atom or a
substituent,
[0032] Het.sup.1 represents a heteroarylene group including a
thiophene ring bonded to a hetero ring including L.sup.W,
[0033] Ar.sup.1 represents an arylene group or a heteroarylene
group, and m represents an integer of 0 to 5, and
[0034] R.sup.1 and R.sup.2 each independently represent an alkyl
group, an aryl group, or a heteroaryl group.
[0035] <2> The photoelectric conversion element as described
in <1>, in which the ring formed by Za is at least one
selected from the group consisting of a pyridine ring, a pyrimidine
ring, a pyrazine ring, a pyridazine ring, a triazine ring, a
tetrazine ring, a quinoline ring, an isoquinoline ring, an
imidazole ring, a pyrazole ring, a triazole ring, a thiazole ring,
an oxazole ring, a benzimidazole ring, a benzotriazole ring, a
benzoxazole ring, and a benzothiazole ring,
[0036] the ring formed by Zb is at least one selected from the
group consisting of a pyridine ring, a pyrimidine ring, a pyrazine
ring, a pyridazine ring, a triazine ring, a tetrazine ring, a
quinoline ring, an isoquinoline ring, an imidazole ring, a triazole
ring, a thiazole ring, an oxazole ring, a benzimidazole ring, a
benzotriazole ring, a benzoxazole ring, and a benzothiazole ring,
and
[0037] the hetero ring including L.sup.W is at least one selected
from the group consisting of a pyridine ring, a pyrimidine ring, a
pyridazine ring, a triazine ring, a tetrazine ring, a quinoline
ring, and an isoquinoline ring.
[0038] <3> The photoelectric conversion element as described
in <1> or <2>, in which M is Ru.sup.2+ or
Os.sup.2+.
[0039] <4> The photoelectric conversion element as described
in any one of <1> to <3>, in which LA is represented by
the following Formula (LA-2),
##STR00003##
[0040] in the formula, Het.sup.1, Ar.sup.1, m, R.sup.1, and R.sup.2
have the same definitions as Het.sup.1, Ar.sup.1, m, R.sup.1, and
R.sup.2, respectively, in Formula (LA-1), and Anc1 and Anc2 each
independently represent an acidic group.
[0041] <5> The photoelectric conversion element as described
in any one of <1> to <4>, in which R.sup.1 and R.sup.2
are all aryl groups or heteroaryl groups.
[0042] <6> The photoelectric conversion element as described
in any one of <1> to <5>, in which Het.sup.1 is a
thiophene ring group represented by any one of the following
Formulae (AR-1) to (AR-3),
##STR00004##
[0043] in the formulae,
[0044] R.sup.L1 to R.sup.L6 each independently represent a hydrogen
atom or a substituent, and R.sup.L1 and R.sup.L2 may be linked to
each other to form a ring, and
[0045] * represents a binding position to a hetero ring including
L.sup.W, and ** represents a binding position to Ar.sup.1 or an N
atom in Formula (LA-1).
[0046] <7> The photoelectric conversion element as described
in any one of <1> to <6>, in which LA is represented by
the following Formula (LA-3),
##STR00005##
[0047] in the formula,
[0048] Y.sup.1 represents an oxygen atom, a sulfur atom, or
--CR.sup.L21.dbd.CR.sup.L22--, R.sup.L7 to R.sup.L22 each
independently represent a hydrogen atom or a substituent, and
adjacent two members of R.sup.L7 to R.sup.L22 may be linked to each
other to form a ring,
[0049] Anc1 and Anc2 each independently represent an acidic group,
and
[0050] n represents 0 or 1.
[0051] <8> The photoelectric conversion element as described
in any one of <1> to <7>, in which the acidic group is
a carboxyl group or a salt thereof.
[0052] <9> The photoelectric conversion element as described
in any one of <1> to <8>, in which LD is a bidentate
ligand represented by any one of the following Formulae (2L-1) to
(2L-4),
##STR00006##
[0053] in the formulae, the ring D.sup.2L represents an aromatic
ring, A.sup.111 to A.sup.141 each independently represent an anion
of a nitrogen atom or an anion of a carbon atom, R.sup.111 to
R.sup.143 each independently represent a hydrogen atom or a
substituent not having an acidic group, and * represents a
coordinating position to the metal ion M.
[0054] <10> The photoelectric conversion element as described
in any one of <1> to <8>, in which LD is a tridentate
ligand represented by any one of the following Formulae (3L-1) to
(3L-4),
##STR00007##
[0055] in the formulae, the ring D.sup.2L represents an aromatic
ring, A.sup.211 to A.sup.242 each independently represent a
nitrogen atom or a carbon atom, in which at least one of each of
A.sup.211 and A.sup.212, A.sup.221 and A.sup.222, A.sup.231 and
A.sup.232, and A.sup.241 and A.sup.242 is an anion, R.sup.211 to
R.sup.241 each independently represent a hydrogen atom or a
substituent not having an acidic group, and * represents a
coordinating position to the metal ion M.
[0056] <11> A dye-sensitized solar cell comprising the
photoelectric conversion element as described in any one of
<1> to <10>.
[0057] <12> A metal complex dye represented by the following
Formula (I),
M(LA)(LD).sub.p(LX).sub.q.(CI).sub.z Formula (I)
[0058] in the formula,
[0059] M represents a metal ion,
[0060] LA represents a tridentate ligand represented by the
following Formula (LA-1),
[0061] LD represents a bidentate or tridentate ligand, and p
represents 0 or 1,
[0062] LX represents a monodentate ligand, and when p is 0, q
represents 3; when p is 1 and LD is a tridentate ligand, q
represents 0; and when p is 1 and LD is a bidentate ligand, q
represents 1, and
[0063] CI represents a counterion necessary for neutralizing the
charge of the metal complex dye, and z represents an integer of 0
to 3; and
##STR00008##
[0064] in the formula,
[0065] Za and Zb each independently represent a non-metal atomic
group necessary for forming a 5- or 6-membered ring, in which at
least one of rings formed by Za and Zb, respectively, has an acidic
group, L.sup.W's each independently represent a nitrogen atom or
CR.sup.W and R.sup.W represents a hydrogen atom or a
substituent,
[0066] Het.sup.1 represents a heteroarylene group including a
thiophene ring bonded to a hetero ring including L.sup.W,
[0067] Ar.sup.1 represents an arylene group or a heteroarylene
group, and m represents an integer of 0 to 5, and
[0068] R.sup.1 and R.sup.2 each independently represent an alkyl
group, an aryl group, or a heteroaryl group.
[0069] <13> A dye solution comprising the metal complex dye
as described in <12> and a solvent.
[0070] <14> A terpyridine compound represented by the
following Formula (LA-2), or an esterified product thereof,
##STR00009##
[0071] in the formula,
[0072] Het.sup.1 represents a heteroarylene group including a
thiophene ring bonded to a pyridine ring,
[0073] Ar.sup.1 represents an arylene group or a heteroarylene
group, and m represents an integer of 0 to 5,
[0074] R.sup.1 and R.sup.2 each independently represent an alkyl
group, an aryl group, or a heteroaryl group, and
[0075] Anc1 and Anc2 each independently represent an acidic
group.
[0076] In the present specification, unless otherwise specified, in
a case where the E configuration or the Z configuration exists in
the molecule for a double bond, the double bond may be either one
of the two configurations or a mixture thereof.
[0077] When there are a plurality of substituents, linking groups,
ligands, or the like (hereinafter referred to as substituents or
the like) represented by specific symbols, or when a plurality of
substituents and the like are defined at the same time, the
respective substituents or the like may be the same as or different
from each another, unless otherwise specified. This also applies to
the definition of the number of substituents or the like. Further,
when a plurality of substituents or the like are close to each
other (in particular, adjacent to each other), they may be linked
to each other to form a ring, unless otherwise specified.
[0078] In the present invention, a ring means the following rings
unless specified otherwise. This also applies to ring groups.
[0079] In the present invention, a ring may be a fused ring. That
is, a ring encompasses a monocycle and a polycycle (fused ring)
formed by the fusion of a plurality of rings. The number of rings
(number of fused rings) forming a polycycle is not particularly
limited, and the rings are preferably, for example, 2- to
5-membered rings.
[0080] Furthermore, in the present invention, a ring encompasses an
aromatic ring and an aliphatic ring.
[0081] In the present invention, an aromatic ring encompasses an
aromatic hydrocarbon ring and an aromatic hetero ring. The aromatic
hydrocarbon ring refers to a hydrocarbon ring exhibiting
aromaticity. Although not being particularly limited, examples of
the ring include a benzene ring as a monocyclic aromatic
hydrocarbon ring, and a naphthalene ring and a fluorene ring as a
polycyclic aromatic hydrocarbon ring. The aromatic hetero ring
refers to a hetero ring exhibiting aromaticity, and encompasses a
monocyclic aromatic hetero ring and a polycyclic aromatic hetero
ring. The aromatic hydrocarbon ring group is also referred to as an
aryl group or arylene group depending on the valence, and
similarly, the aromatic hetero ring group is also referred to as a
heteroaryl group or a heteroarylene group.
[0082] The aliphatic ring refers to a ring other than an aromatic
ring, and encompasses an aliphatic hydrocarbon ring and an
aliphatic hetero ring. Examples of the aliphatic hydrocarbon ring
include a saturated hydrocarbon ring, and an unsaturated
hydrocarbon ring not exhibiting aromaticity. Examples thereof
include a saturated monocyclic hydrocarbon ring (cycloalkane), a
saturated polycyclic hydrocarbon ring, an unsaturated monocyclic
hydrocarbon ring (cycloalkene and cycloalkyne), and an unsaturated
polycyclic hydrocarbon ring.
[0083] The aromatic hetero ring and the aliphatic hetero ring may
be collectively referred to as a hetero ring in some cases. The
hetero ring refers to a ring having carbon atoms and a heteroatom
(for example, a nitrogen atom, an oxygen atom, a sulfur atom, a
silicon atom, a selenium atom, and a phosphorus atom) as
ring-constituting atoms.
[0084] In the present specification, expressions of a compound
(including a complex and a dye) are used to mean inclusion of, in
addition to the compound itself, salts and ions of the compound.
Further, within a range exhibiting desired effects, the expressions
are used to mean inclusion of modifications of a part of the
structure. In addition, a compound in which substitution or
non-substitution is not explicitly described is used to mean
inclusion of compounds which have arbitrary substituents within a
range exhibiting the desired effects. This also applies to
substituents, linking groups, and ligands.
[0085] Moreover, in the present specification, a numerical value
range represented by "(a value) to (a value)" means a range
including the numerical values indicated before and after "to" as a
lower limit value and an upper limit value, respectively.
[0086] The photoelectric conversion element and the dye-sensitized
solar cell of the present invention each have a metal complex dye
having a tridentate ligand in which an amino group-containing
heteroarylene group is introduced at the ring-constituting atom at
the 4-position with respect to a ring-constituting nitrogen atom
coordinating to a metal ion in a nitrogen-containing ring. Thus,
they are less affected by the film thickness of the semiconductor
layer, and exhibit excellent photoelectric conversion efficiency
and high durability. Therefore, according to the present invention,
it is possible to provide a photoelectric conversion element and a
dye-sensitized solar cell, each of which is less affected by the
film thickness of a semiconductor layer, exhibits excellent
photoelectric conversion efficiency, particularly when the film
thickness is small, and has high durability; and a metal complex
dye, a dye solution, and a terpyridine compound or an esterified
product thereof, each of which is used in the photoelectric
conversion element and the dye-sensitized solar cell.
[0087] The above or other characteristics and advantages of the
present invention will be further clarified from the following
description with reference to drawings appropriately attached
hereto.
BRIEF DESCRIPTION OF THE DRAWINGS
[0088] FIG. 1 is a cross-sectional view schematically showing a
photoelectric conversion element in the first aspect of the present
invention, including an enlarged view of the circled portion in the
layer thereof, in a system in which the photoelectric conversion
element is applied in cell uses.
[0089] FIG. 2 is a cross-sectional view schematically showing a
dye-sensitized solar cell including a photoelectric conversion
element in the second aspect of the present invention.
[0090] FIG. 3 is a view showing the visible absorption spectrum (a
DMF solution) of the metal complex dye (D-1) synthesized in
Examples of the present invention.
[0091] FIG. 4 is a view showing the visible absorption spectrum (a
tetrabutylammonium hydroxide solution) of the metal complex dye
(D-1) synthesized in Examples of the present invention.
[0092] FIG. 5 is a view showing the visible absorption spectrum in
semiconductor fine particles (titanium oxide) onto which the metal
complex dye (D-1) synthesized in Examples of the present invention
is adsorbed.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0093] [Photoelectric Conversion Element and Dye-Sensitized Solar
Cell]
[0094] The photoelectric conversion element of the present
invention has an electrically conductive support, a photoconductor
layer including an electrolyte, a charge transfer layer including
an electrolyte, and a counter electrode (opposite electrode). The
photoconductor layer, the charge transfer layer, and the counter
electrode are provided in this order on the electrically conductive
support.
[0095] In the photoelectric conversion element of the present
invention, at least a portion of the semiconductor fine particles
forming the photoconductor layer carries a metal complex dye
represented by Formula (I) which will be described later, as a
sensitizing dye. Here, the aspect in which the metal complex dye is
carried on the surface of the semiconductor fine particles
encompasses an aspect in which the metal complex dye is deposited
on the surface of the semiconductor fine particles, an aspect in
which the metal complex dye is adsorbed onto the surface of the
semiconductor fine particles, and a mixture of the aspects. The
adsorption includes chemical adsorption and physical adsorption,
with the chemical adsorption being preferable.
[0096] The semiconductor fine particles may carry other metal
complex dyes, together with the metal complex dye of Formula (I)
which will be described later.
[0097] The semiconductor fine particles preferably carry a
co-adsorbent which will be described later, together with the metal
complex dye.
[0098] Moreover, the photoconductor layer includes an electrolyte.
The electrolyte included in the photoconductor layer may be the
same as or different from the electrolyte included in the charge
transfer layer, but they are preferably the same. Here, the
expression "electrolytes are the same" is used to mean inclusion of
both of an aspect in which the components included in the
electrolyte of the photoconductor layer are the same as the
components included in the electrolyte of the charge transfer layer
and the contents of both the components are the same, and an aspect
in which the components included in the electrolyte of the
photoconductor layer are the same as the components included in the
electrolyte of the charge transfer layer but the contents of both
the components are different.
[0099] The photoelectric conversion element of the present
invention is not particularly limited in terms of configurations
other than the configuration defined in the present invention, and
may adopt known configurations regarding photoelectric conversion
elements. The respective layers constituting the photoelectric
conversion element of the present invention are designed depending
on purposes, and may be formed into, for example, a single layer or
multiple layers. Further, layers other than the layers may be
included, as necessary.
[0100] The dye-sensitized solar cell of the present invention is
formed by using the photoelectric conversion element of the present
invention.
[0101] Hereinafter, preferred embodiments of the photoelectric
conversion element and the dye-sensitized solar cell of the present
invention will be described.
[0102] A system 100 shown in FIG. 1 is a system in which a
photoelectric conversion element 10 in the first aspect of the
present invention is applied in cell uses where an operating means
M (for example, an electric motor) in an external circuit 6 is
forced to work.
[0103] The photoelectric conversion element 10 includes
semiconductor fine particles 22 sensitized by carrying an
electrically conductive support 1 and a dye (metal complex dye) 21,
a photoconductor layer 2 including an electrolyte between the
semiconductor fine particles 22, a charge transfer layer 3 that is
a hole transport layer, and a counter electrode 4.
[0104] In the photoelectric conversion element 10, the
light-receiving electrode 5 has the electrically conductive support
1 and the photoconductor layer 2, and functions as a functional
electrode.
[0105] In the system 100 in which the photoelectric conversion
element 10 is applied, light incident to the photoconductor layer 2
excites the metal complex dye 21. The excited metal complex dye 21
has electrons having high energy, and these electrons are
transferred from the metal complex dye 21 to a conduction band of
the semiconductor fine particles 22, and further reach the
electrically conductive support 1 by diffusion. At this time, the
metal complex dye 21 is in an oxidized form (cation). While the
electrons reaching the electrically conductive support 1 work in an
external circuit 6, they reach the oxidized form of the metal
complex dye 21 through the counter electrode 4 and the charge
transfer layer 3, and reduce the oxidized form, whereby the system
100 functions as a solar cell.
[0106] A dye-sensitized solar cell 20 shown in FIG. 2 is
constituted with a photoelectric conversion element in the second
aspect of the present invention.
[0107] With respect to the photoelectric conversion element shown
in FIG. 1, the photoelectric conversion element which becomes the
dye-sensitized solar cell 20 is different in the configurations of
the electrically conductive support 41 and the photoconductor layer
42, and also differs in that it has a spacer S, but except for
these, has the same structure as the photoelectric conversion
element 10 shown in FIG. 1. That is, the electrically conductive
support 41 has a bilayered structure including a substrate 44 and a
transparent electrically-conductive film 43 which is formed on the
surface of the substrate 44. Further, the photoconductor layer 42
has a bilayered structure including a semiconductor layer 45 and a
light-scattering layer 46 which is formed adjacent to the
semiconductor layer 45. A spacer S is provided between the
electrically conductive support 41 and the counter electrode 48. In
the dye-sensitized solar cell 20, 40 is a light-receiving
electrode, and 47 is a charge transfer layer.
[0108] In a similarly manner to the system 100 in which the
photoelectric conversion element 10 is applied, the dye-sensitized
solar cell 20 functions as a solar cell by light incident on the
photoconductor layer 42.
[0109] The photoelectric conversion element and the dye-sensitized
solar cell of the present invention are not limited to the above
preferred aspects, and the configuration of each of the aspects can
be combined as appropriate within a range not departing from the
scope of the present invention.
[0110] In the present invention, the materials and the respective
members for use in the photoelectric conversion element and the
dye-sensitized solar cell can be prepared by ordinary methods.
Reference can be made to, for example, U.S. Pat. Nos. 4,927,721A,
4,684,537A, 5,084,365A, 5,350,644A, 5,463,057A, 5,525,440A,
JP1995-249790A (JP-H07-249790A), JP2001-185244A, JP2001-210390A,
JP2003-217688A, JP2004-220974A, and JP2008-135197.
[0111] <Metal Complex Dye Represented by Formula (I)>
[0112] The metal complex dye of the present invention is
represented by the following Formula (I). The metal complex dye of
the present invention can impart a less effect of a change in the
film thickness in the semiconductor layer, high photoelectric
conversion efficiency, and excellent heat stability to the
photoelectric conversion element and the dye-sensitized solar cell
by including a ligand LA represented by the following Formula
(LA-1). Accordingly, the metal complex dye of the present invention
is preferably used as a sensitizing dye in the dye-sensitized solar
cell.
M(LA)(LD).sub.p(LX).sub.q.(CI).sub.z Formula (I)
[0113] In Formula (I),
[0114] M represents a metal ion,
[0115] LA represents a tridentate ligand represented by the
following Formula (LA-1),
##STR00010##
[0116] in the formula,
[0117] Za and Zb each independently represent a non-metal atomic
group necessary for forming a 5- or 6-membered ring, in which at
least one of rings formed by Za and Zb, respectively, has an acidic
group, L.sup.W's each independently represent a nitrogen atom or
CR.sup.W, and R.sup.W represents a hydrogen atom or a
substituent,
[0118] Het.sup.1 represents a heteroarylene group including a
thiophene ring bonded to a hetero ring including L.sup.W,
[0119] Ar.sup.1 represents an arylene group or a heteroarylene
group, and m represents an integer of 0 to 5, and is preferably 0
or 1, and
[0120] R.sup.1 and R.sup.2 each independently represent an alkyl
group, an aryl group, or a heteroaryl group.
[0121] In the present specification, the
"Het.sup.1-(Ar.sup.1)m-NR.sup.1R2" group is referred to as an
"amino group-containing heteroarylene group".
[0122] LD represents a bidentate or tridentate ligand. p represents
0 or 1.
[0123] LX represents a monodentate ligand. When p is 0, q
represents 3; when p is 1 and LD is a tridentate ligand, q
represents 0; and when p is 1 and LD is a bidentate ligand, q
represents 1.
[0124] CI represents a counterion necessary for neutralizing the
charge of the metal complex dye. z represents an integer of 0 to 3,
and is preferably 0 or 1, and more preferably 0.
[0125] --Metal Ion M--
[0126] M is a central metal ion of the metal complex dye, and
examples thereof include ions of elements belonging to Groups 6 to
12 on the long-form periodic table of the elements. Examples of
such metal ions include respective ions of Ru, Fe, Os, Cu, W, Cr,
Mo, Ni, Pd, Pt, Co, Ir, Rh, Re, Mn, and Zn. The metal ion M may be
one kind of ion, or two or more kinds of ions.
[0127] In the present invention, the metal ion M is preferably
Os.sup.2+, Ru.sup.2+, or Fe.sup.2+, more preferably Os.sup.2+ or
Ru.sup.2+, and among these, Ru.sup.2+ is particularly preferable.
In addition, in a state of being incorporated in the photoelectric
conversion element, the valence of M may be changed by the redox
reaction with the surrounding material.
[0128] --Ligand LA--
[0129] The ligand LA is a tridentate ligand (compound) which is
represented by Formula (LA-1) and coordinates to a metal ion M
through three nitrogen atoms in Formula (LA-1).
[0130] This ligand LA has at least one acidic group (also referred
to as an adsorptive group) and makes the metal complex dye of the
present invention carried on semiconductor fine particles.
[0131] The ligand LA has an amino group-containing heteroarylene
group on the ring-constituting carbon atom at the 4-position with
respect to a ring-constituting nitrogen atom that coordinates to a
metal ion of a ring formed of a nitrogen atom, a carbon atom, and
L.sup.W (also referred to as a terminal nitrogen-containing ring or
a hetero ring including L.sup.W). In the ligand LA, if the amino
group-containing heteroarylene group is bonded to the
ring-constituting carbon atom at the 4-position of the hetero ring
including L.sup.W, the absorbance of a metal complex dye having the
ligand LA increases. A photoelectric conversion element and a
dye-sensitized solar cell, each containing the metal complex dye
having enhanced absorbance in the photoconductor layer, have
improved photoelectric conversion efficiency. Further, even when
the film thickness of a semiconductor layer that will provide a
photoconductor layer is small, excellent photoelectric conversion
efficiency is exhibited. Moreover, the durability of the
photoelectric conversion element and the dye-sensitized solar cell
is also improved. Accordingly, this ligand LA is preferably used as
a ligand of a metal complex dye for use in a dye-sensitized solar
cell.
[0132] In Formula (LA-1), Za and Zb each independently represent a
non-metal atomic group necessary for forming a 5-membered ring or a
6-membered ring. Za and Zb are each preferably a non-metal atomic
group selected from a carbon atom and the heteroatoms, and more
preferably a non-metal atomic group selected from a carbon atom, a
nitrogen atom, an oxygen atom, a sulfur atom, and a phosphorus
atom.
[0133] The rings formed by Za and Zb are preferably an aromatic
hetero ring as a 5-membered ring and an aromatic hetero ring as a
6-membered ring. These rings encompass a monocycle as well as a
fused ring formed by the fusion of at least one of an aromatic ring
or an aliphatic ring to the monocycle. Further, the ring formed by
Za and the ring formed by Zb may have a substituent, which is
preferably selected from the substituent group T which will be
described later. A fused ring in which the rings formed by Za and
Zb are bonded through this substituent may be formed. Examples of
such a fused ring include a 1,10-phenanthroline ring.
[0134] The aromatic hetero ring as a 5-membered ring may be any one
of 5-membered rings including the heteroatom as a ring-constituting
atom. It is preferably, for example, at least one of a pyrazole
ring, an imidazole ring, a triazole ring, a thiazole ring, an
oxazole ring, a benzimidazole ring, a benzotriazole ring, a
benzoxazole ring, and a benzothiazole ring. The aromatic hetero
ring as a 6-membered ring may be any one of 6-membered rings
including the heteroatom as a ring-constituting atom. It is
preferably, for example, at least one of a pyridine ring, a
pyrimidine ring, a pyrazine ring, a pyridazine ring, a triazine
ring, a tetrazine ring, a quinoline ring, and an isoquinoline
ring.
[0135] The rings formed by Za and Zb are each at least one selected
from the group consisting of the group including the aromatic
hetero rings as a 5-membered ring and the group including the
aromatic hetero rings as a 6-membered ring, and aromatic hetero
rings which are suitable for the structures of the respective rings
represented by Formula (LA-1) are preferably selected.
[0136] The ring formed by Za is preferably at least one selected
from the group consisting of a pyridine ring, a pyrimidine ring, a
pyrazine ring, a pyridazine ring, a triazine ring, a tetrazine
ring, a quinoline ring, an isoquinoline ring, an imidazole ring, a
pyrazole ring, a triazole ring, a thiazole ring, an oxazole ring, a
benzimidazole ring, a benzotriazole ring, a benzoxazole ring, and a
benzothiazole ring.
[0137] The ring formed by Zb is preferably at least one selected
from the group consisting of a pyridine ring, a pyrimidine ring, a
pyrazine ring, a pyridazine ring, a triazine ring, a tetrazine
ring, a quinoline ring, an isoquinoline ring, an imidazole ring, a
triazole ring, a thiazole ring, an oxazole ring, a benzimidazole
ring, a benzotriazole ring, a benzoxazole ring, and a benzothiazole
ring.
[0138] Among those, the hetero rings formed by Za and Zb are more
preferably each an imidazole ring, a pyridine ring, or a pyrimidine
ring, and particularly preferably are both pyridine rings.
[0139] At least one of the hetero rings formed by Za and Zb has an
acidic group. Each of the hetero rings formed by Za and Zb may or
may not have a substituent other than the acidic group. Examples of
the substituent which may be contained in these hetero rings
include groups selected from the substituent group T which will be
described later.
[0140] In the present invention, the acidic group is a substituent
which has a dissociative proton and has a pKa of 11 or less. The
pKa of the acidic group can be determined in accordance with the
"SMD/M05-2X/6-31G*" method described in J. Phys. Chem. A2011, 115,
pp. 6641-6645. Examples thereof include: an acid group showing
acidity, such as a carboxyl group, a phosphonyl group, a phosphoryl
group, a sulfo group, and a boric acid group; or groups having
these acidic groups. Examples of the group having an acid group
include groups having an acid group and a linking group. The
linking group is not particularly limited, and examples thereof
include a divalent group, and preferably an alkylene group, an
alkenylene group, an alkynylene group, an arylene group, and a
heteroarylene group. This linking group may have a group selected
from the substituent group T which will be described later as a
substituent. Preferred examples of the acidic group having an acid
group and a linking group include carboxymethyl, carboxyvinylene,
dicarboxyvinylene, cyanocarboxyvinylene, 2-carboxy-1-propenyl,
2-carboxy-1-butenyl, and carboxyphenyl.
[0141] The acidic group is preferably a carboxyl group, a
phosphonyl group, a sulfo group, or a group having a carboxyl
group, and more preferably a carboxyl group.
[0142] The acidic group may be in the form of a dissociated anion
due to release of a proton or in the form of a salt when the acidic
group is included in the metal complex dye represented by Formula
(I). When the acidic group is in the form of a salt, the counterion
is not particularly limited, and examples thereof include those
exemplified as positive ions in the following counterion CI.
[0143] In addition, the acidic group may be esterified as described
later.
[0144] At least one of the hetero rings formed by Za and Zb has an
acidic group. It is preferable that all of the hetero rings formed
by Za and Zb have at least one acidic group. The number of acidic
groups contained in each of the rings formed by Za and Zb is
preferably 1 to 3, more preferably 1 or 2, and still more
preferably 1, and particularly preferably, each of the rings has an
acidic group.
[0145] The substitution position of the acidic group is not
particularly limited. For example, in a case where the rings formed
by Za and Zb are each a 6-membered ring, examples of the
substitution position include a ring-constituting atom at the
4-position of the ring-constituting nitrogen atom that coordinates
to the metal ion M.
[0146] In Formula (LA-1), the hetero ring including L.sup.W
encompasses a monocycle and a fused ring, and in a case where the
hetero ring including L.sup.W is a fused ring, a fused ring with
the hetero ring formed by Zb is also encompassed.
[0147] L.sup.W represents a nitrogen atom or CR.sup.W. R.sup.W
represents a hydrogen atom or a substituent, with a hydrogen atom
being preferable. The substituent which can be adopted as R.sup.W
is not particularly limited, and examples thereof include a group
selected from the substituent group T which will be described later
(preferably excluding the following amino group-containing
heteroarylene group). In a case where the hetero ring including
L.sup.W has a plurality of R.sup.W's, R.sup.W's may be bonded to
each other to form a ring.
[0148] As the hetero ring including L.sup.W, an aromatic hetero
ring which is suitable for the ring structure in Formula (LA-1) is
preferably selected from the aromatic hetero rings as 6-membered
rings, described as the hetero rings formed by Za and Zb. The
hetero ring is more preferably at least one of a pyridine ring, a
pyrimidine ring, a pyridazine ring, a triazine ring, a tetrazine
ring, a quinoline ring, or an isoquinoline ring, still more
preferably a pyridine ring or a pyrimidine ring, and particularly
preferably a pyridine ring.
[0149] The "Het.sup.1" in amino group-containing heteroarylene
group is a heteroarylene group including a thiophene ring bonded to
a hetero ring including L.sup.W. The heteroarylene group may be any
of groups bonded to the hetero ring including L.sup.W with a
thiophene ring. Examples of such a heteroarylene group include, in
addition to the monocyclic thiophene ring groups, a fused
polycyclic hetero ring group including a thiophene ring bonded to
the hetero ring including L.sup.W, and at least one ring which is
fused to the thiophene ring.
[0150] The fused polycyclic hetero ring group is not particularly
limited, but examples thereof include a ring group formed by the
fusion of a plurality of thiophene ring groups, and a ring group
formed by the fusion of a plurality of thiophene rings with
aromatic rings or aliphatic rings. The aromatic ring and the
aliphatic ring are each not particularly limited, but an aromatic
hydrocarbon ring and an aromatic hetero ring are preferable. The
aromatic hydrocarbon ring is as described above, and is preferably
a benzene ring. Examples of the aromatic hetero ring include an
aromatic hetero ring as a 5- or 6-membered ring, described as the
hetero rings formed by Za and Zb, with a thiophene ring being
preferable.
[0151] Here, the number of rings to be fused is not particularly
limited, and is, for example, preferably 2 to 5.
[0152] Examples of the fused polycyclic hetero ring group include
the respective ring groups of a benzothiophene ring, a
benzoisothiophene ring, a thienopyridine ring,
cyclopentadithiophene ring, a thieno[3,2-b]thiophene ring, a
thieno[3,4-b]thiophene ring, a trithiophene ring, a
benzodithiophene ring, a dithienopyrrole ring, a dithienosilole
ring, and the like.
[0153] Among those, a benzothiophene ring group, a
cyclopentadithiophene ring group, a thieno[3,2-b]thiophene ring
group, a thieno[3,4-b]thiophene ring group, a trithiophene ring
group, a benzodithiophene ring group, a dithienopyrrole ring group,
or a dithienosilole ring group is preferable.
[0154] Het.sup.1 may have a substituent. Such a substituent is not
particularly limited, and examples thereof include a group selected
from the substituent group T which will be described later. The
substituent is preferably an alkyl group, an alkoxy group, an
alkylthio group, or the like. In a case where Het.sup.1 has a
plurality of substituents, adjacent substituents may be bonded to
each other to form a ring together with a ring-constituting atom of
Het.sup.1. Preferred examples of the group capable of forming such
a ring include an alkylenedioxy group (an --O--R.sup.ve--O-- group)
in which two alkoxy groups are linked to each other. Rye represents
an alkylene group, and examples thereof include ethylene and
propylene.
[0155] Het.sup.1 is preferably a thiophene ring group represented
by any one of the following Formulae (AR-1) to (AR-3), and more
preferably a thiophene ring group represented by Formula
(AR-1).
##STR00011##
[0156] In the formulae, R.sup.L1 to R.sup.L6 each independently
represent a hydrogen atom or a substituent. The substituent which
can be taken by R.sup.L1 to R.sup.L6 has the same definition as the
substituent which can be contained in Het.sup.1, and preferred
examples thereof are also the same.
[0157] R.sup.L1, R.sup.L3, R.sup.L5, and R.sup.L6 are each still
more preferably a hydrogen atom, an alkoxy group, or an alkylthio
group. If R.sup.L1, R.sup.L3, R.sup.L5, and R.sup.L6 are each any
one of these substituents, the photoelectric conversion efficiency
is improved.
[0158] Incidentally, R.sup.L1 and R.sup.L2 may be linked to each
other to form a ring. Examples of the ring formed by the linking of
R.sup.L1 and R.sup.L2 include an aromatic ring and an aliphatic
ring. The ring is preferably a hetero ring formed by the bonding of
a ring-constituting carbon atom bonded to R.sup.L1 and R.sup.L2 and
an alkylenedioxy group. Here, the alkylene group is preferably
ethylene or propylene.
[0159] * represents a binding position to a hetero ring including
L.sup.W (a core of the ligand LA).
[0160] ** represents a binding position to Ar.sup.1 or an N atom of
Formula (LA-1).
[0161] "Ar.sup.1" of the amino group-containing heteroarylene group
is an arylene group or a heteroarylene group.
[0162] The arylene group Ar.sup.1 is not particularly limited, and
may be a monocycle or a fused ring. Preferred examples thereof
include the respective groups of a benzene ring, a naphthalene
ring, an anthracene ring, a phenanthrene ring, and a fluorene
ring.
[0163] The heteroarylene group Ar.sup.1 is not particularly
limited, and may be a group which is the same as or different from
the heteroarylene group Het.sup.1.
[0164] In a case where the heteroarylene group Ar.sup.1 is a ring
group which is the same ring as the heteroarylene group Het.sup.1,
the group is as described above.
[0165] In a case where the heteroarylene group Ar.sup.1 is a ring
group which is different from the heteroarylene group Het.sup.1,
examples thereof include a hetero ring group as a 5-membered ring
other than a monocyclic thiophene ring, a 6-membered or higher
hetero ring group, and a fused polycyclic hetero ring group
including a hetero ring group (excluding a thiophene ring group) in
which a ring bonded to Het.sup.1 or an N atom is 5-membered or
higher. The hetero ring group is preferably a group as a 5- or
6-membered ring.
[0166] Examples of the monocyclic 5-membered hetero ring group
include the respective groups of a furan ring, a pyrrole ring, a
selenophene ring, a thiazole ring, an oxazole ring, an isothiazole
ring, an isoxazole ring, an imidazole ring, a pyrazole ring, a
thiadiazole ring, an oxadiazole ring, a silole ring, a triazole
ring, and the like. Among those, a furan ring group is
preferable.
[0167] The monocyclic 6-membered hetero ring group is not
particularly limited, and examples thereof include the respective
groups of a pyridine ring, a pyrazine ring, a pyrimidine ring, a
pyridazine ring, a triazine ring, a tetrazine ring, and the
like.
[0168] The fused polycyclic hetero ring group including a hetero
ring group (excluding a thiophene ring group) in which a ring
bonded to Het.sup.1 or an N atom is 5-membered or higher is not
particularly limited, and examples thereof include a ring group
formed by the fusion of a plurality of monocyclic 5-membered or
higher hetero ring groups, and a ring group formed by the fusion of
a plurality of monocyclic 5-membered or higher hetero rings and
aromatic or aliphatic rings. As the fused polycyclic hetero ring
group as Ar.sup.1, a ring group formed by the fusion of a plurality
of the same or different rings selected from the group consisting
of the respective ring groups of a benzene ring, a thiophene ring,
a furan ring, a pyrrole ring, a selenophene ring, a thiazole ring,
an oxazole ring, an isothiazole ring, an isoxazole ring, an
imidazole ring, a pyrazole ring, a thiadiazole ring, an oxadiazole
ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a
pyridazine ring, a triazine ring, and a tetrazine ring is
preferable. Here, the number of rings to be fused is not
particularly limited, and is preferably, for example, 2 to 5.
[0169] Examples of such a fused polycyclic hetero ring group
include the respective ring groups of a benzofuran ring, an
isobenzofuran ring, a benzimidazole ring, an indazole ring, an
indole ring, an isoindole ring, an indolizine ring, a quinoline
ring, a carbazole ring, an acridine ring, and the like.
[0170] The heteroarylene group Ar.sup.1 is preferably an arylene
group or a monocyclic 5-membered hetero ring group, more preferably
a benzene ring, a furan ring, or a thiophene ring, and particularly
preferably a benzene ring or a thiophene ring.
[0171] Ar.sup.1 may have a substituent. Such a substituent is not
particularly limited and has the same definition as the substituent
which may be contained in Het.sup.1, and preferred examples thereof
are also the same.
[0172] Furthermore, Ar.sup.1 may be bonded to one of R.sup.1 and
R.sup.2 which will be described later to form a ring. The ring
formed by the bonding of Ar.sup.1, N, and one of R.sup.1 and
R.sup.2 is not particularly limited, and may be an aromatic ring or
an aliphatic ring. Examples of such a ring include an aryl group
having a structure of the "nitrogen-containing ring group" which
will be described later, and the ring is preferably a carbazole
ring, an acridane ring, a phenoxazine ring, a phenothiazine ring,
or the like.
[0173] R.sup.1 and R.sup.2 each independently represent an alkyl
group, an aryl group, or a heteroaryl group.
[0174] The number of carbon atoms in the alkyl group is preferably
1 to 24, and more preferably 1 to 12. Further, the alkyl group may
be either linear or branched. Examples of the alkyl group include
methyl, ethyl, isopropyl, n-butyl, t-butyl, isobutyl, n-hexyl,
n-octyl, 2-ethylhexyl, 3,7-dimethyloctyl, 2-butyloctyl, n-dodecyl,
n-hexadecyl, and 2-hexyldecyl, and preferably t-butyl, n-hexyl,
2-ethylhexyl, and n-octyl.
[0175] The number of carbon atoms in the aryl group is preferably 6
to 24, and more preferably 6 to 18. In the present invention, the
aryl group may be any one of groups formed of an aromatic
hydrocarbon ring, or may be a fused ring group formed by fusion of
at least one of different aromatic hydrocarbon rings and aliphatic
hydrocarbon rings. Examples of the aryl group include phenyl,
naphthyl, fluorenyl, and anthracenyl. The aryl group of R.sup.1 and
R.sup.2 is preferably phenyl, naphthyl, or fluorenyl, and more
preferably phenyl.
[0176] The number of carbon atoms in the heteroaryl group is
preferably 0 to 24, and more preferably 1 to 18. The hetero ring
that forms a heteroaryl group is not particularly limited, and
examples thereof include the respective rings described as
heteroarylene group Het.sup.1 and the respective rings described as
the heteroarylene group Ar.sup.1.
[0177] It is preferable that at least one of R.sup.1 and R.sup.2 is
an aryl group or a heteroaryl group, and in view of photoelectric
conversion efficiency, it is more preferable that R.sup.1 and
R.sup.2 are all aryl groups or heteroaryl groups, and it is
particularly preferable that R.sup.1 and R.sup.2 are all aryl
groups.
[0178] R.sup.1 and R.sup.2 may not be bonded to each other, or may
be bonded to each other to form a ring. The nitrogen-containing
ring group formed by the bonding of R.sup.1 and R.sup.2 is not
particularly limited, and it may be an aromatic ring or an
aliphatic ring. Examples of such a nitrogen-containing ring group
include a morpholine ring group, a thiomorpholine ring group, a
piperidine ring group, an indole ring group, or the following
respective nitrogen-containing ring groups.
##STR00012##
[0179] Here, R.sup.DA3 and R.sup.DA4 each independently represent
an alkyl group or an aryl group. The alkyl group and the aryl group
have the same definitions as the alkyl group and the aryl group of
R.sup.1 and R.sup.2, respectively, and preferred examples thereof
are also the same.
[0180] The respective nitrogen-containing ring groups may each have
a substituent. Examples of the substituent which may be contained
in these rings include a substituent selected from the substituent
group T which will be described later. Further, the number of the
substituents is not particularly limited. In a case where the ring
group has a plurality of substituents, the substituents may be the
same as or different from each other.
[0181] R.sup.1 and R.sup.2 may each have a substituent. The
substituent which may be each contained in R.sup.1 and R.sup.2 is
not particularly limited, and examples thereof include a group
selected from the substituent group T which will be described
later. Among those, an alkyl group, an aryl group, an alkoxy group,
an alkylthio group, a silyl group, a halogen atom, or an amino
group is preferable, and an alkoxy group or an alkylthio group is
more preferable.
[0182] The N,N-dialkylamino group in which R.sup.1 and R.sup.2 are
both alkyl groups is not particularly limited, and examples thereof
include N,N-dimethylamino, N,N-diethylamino, N,N-dipropylamino,
N,N-dipentylamino, N,N-bis(n-hexyl)amino, N-methyl-N-n-hexylamino,
N,N-didecylamino, N,N-bis(2-ethylhexyl)amino,
N,N-bis(n-octyl)amino, and N,N-bis(n-decyl)amino.
[0183] The N,N-diarylamino group in which R.sup.1 and R.sup.2 are
both aryl groups is not particularly limited, and examples thereof
include N,N-diphenylamino, N,N-di(4-methylphenyl)amino,
N,N-di(4-(t-butyl)phenyl)amino, N,N-di(4-(n-hexyl)phenyl)amino,
N,N-di(4-methoxyphenyl)amino, N,N-di(4-(n-octyloxy)phenyl)amino,
N,N-di(4-trimethylsilylphenyl)amino,
N,N-di(3,5-dimethylphenyl)amino,
N,N-di(4-dimethylaminophenyl)amino,
N,N-di(4-methylthiophenyl)amino, N,N-di(4-biphenyl)amino,
N,N-dinaphthylamino, N,N-difluorenylamino,
N,N-di(4-diphenylaminophenyl)amino, N,N-di(4-fluorophenyl)amino,
N,N-di(4-trifluoromethylphenyl)amino, N,N-di(4-chlorophenyl)amino,
N-methoxyphenyl-N-naphthylamino, and
4,7-di(t-butylcarbazoyl)amino.
[0184] Examples of the N,N-diheteroarylamino group in which R.sup.1
and R.sup.2 are both heteroaryl groups include N,N-dithienylamino,
N,N-di(4-alkylthienyl)amino, N,N-di(4-(n-hexyl)thienyl)amino, and
N,N-di(3-pyridyl)amino.
[0185] The ligand LA is preferably a tridentate ligand (terpyridine
compound) represented by the following Formula (LA-2).
##STR00013##
[0186] In the formula, Het.sup.1, Ar.sup.1, m, R.sup.1, and R.sup.2
have the same definitions as Het.sup.1, Ar.sup.1, m, R.sup.1, and
R.sup.2, respectively, in Formula (LA-1), and preferred examples
thereof are also the same. Here, Het.sup.1 is bonded to a pyridine
ring with the thiophene ring in Het.sup.1.
[0187] Anc1 and Anc2 each independently represent an acidic group.
The acidic group has the same definition as the acidic group of
Formula (LA-1), and preferred examples thereof are also the
same.
[0188] The terpyridine compound is the ligand LA itself, but in the
present invention, the ligand LA can also be used as a precursor
compound of the ligand LA as described later. Accordingly, in the
present invention, the term, a ligand LA, encompasses a precursor
compound of the ligand LA, in addition to the ligand LA itself (the
terpyridine compound). Preferred examples of the precursor compound
include an esterified product in which at least one of Anc1 and
Anc2 of the terpyridine compound is esterified (also referred to as
an esterified product of the terpyridine compound).
[0189] This esterified product is a compound having the acidic
group protected, which is an ester capable of being regenerated
into an acidic group by hydrolysis or the like, and is not
particularly limited. Examples thereof include an alkyl esterified
product, an aryl esterified product, and a heteroaryl esterified
product of the acidic group. Among these, the alkyl esterified
product is preferable. The alkyl group which forms an alkyl
esterified product is not particularly limited, but an alkyl group
having 1 to 10 carbon atoms is preferable, an alkyl group having 1
to 6 carbon atoms is more preferable, and an alkyl group having 1
to 4 carbon atoms is still more preferable. The aryl group which
forms an aryl esterified product and the heteroaryl group which
forms a heteroaryl esterified product are each not particularly
limited, and examples thereof include the substituent group T which
will be described later. These groups may have at least one
substituent selected from the substituent group T which will be
described later.
[0190] It is preferable that two of Anc1 and Anc2 are used as the
acidic group to be esterified. In this case, the two esters may be
the same as or different from each other.
[0191] The ligand LA is more preferably a tridentate ligand
represented by the following Formula (LA-3). The tridentate ligand
represented by Formula (LA-3) has an amino group-containing
heteroaryl group formed by the combination of a thiophene ring with
an N,N-diarylamino group. If such a tridentate ligand LA is
introduced into a metal complex dye contained in a photoconductor
layer of a photoelectric conversion element and a dye-sensitized
solar cell, the photoelectric conversion efficiency and the
durability become more excellent.
##STR00014##
[0192] In the formula, Y.sup.1 represents any one of an oxygen
atom, a sulfur atom, or --CR.sup.L21=CR.sup.L22--, with a sulfur
atom being preferable.
[0193] R.sup.L7 to R.sup.L22 each independently represent a
hydrogen atom or a substituent. Adjacent two members of R.sup.L7 to
R.sup.L22 may be linked to each other to form a ring. Further,
R.sup.L7 to R.sup.L22 each have the same definition as R.sup.L1,
and preferred examples thereof are also the same. R.sup.L7 to
R.sup.L22 may each have a substituent, the substituent has the same
definition as the substituent which may be contained in R.sup.1 and
R.sup.2, and preferred examples thereof are also the same.
[0194] Anc1 and Anc2 each independently represent an acidic group.
The acidic group has the same definition as the acidic group of
Formula (LA-1), and preferred examples thereof are also the
same.
[0195] n represents 0 or 1.
[0196] The esterified product of the terpyridine compound
represented by Formula (LA-3) has the same definition as esterified
product of the terpyridine compound represented by Formula (LA-2),
and preferred examples thereof are also the same.
[0197] The ligand LA can be synthesized in accordance with ordinary
methods. For example, the ligand LA represented by Formula (L1-4)
can be synthesized by subjecting a compound represented by Formula
(L1-1) and a compound represented by Formula (L1-2) to a coupling
reaction, and hydrolyzing an ester group of a precursor compound
represented by Formula (L1-3), as shown in the following scheme. In
this synthesis method, an esterified product of a carboxyl group is
shown as the precursor compound, but the present invention is not
limited thereto, and any of precursor compounds obtained by
esterification of any one of the acidic groups may be used.
[0198] The coupling reaction herein can be carried out by, for
example, "a Stille coupling reaction", a "Suzuki coupling method"
described in "Experimental Chemistry Course, Fifth Edition",
Maruzen Co., Ltd., edited by The Chemical Society of Japan, Vol.
13, pp. 92-117, or methods equivalent thereto. Further, the
hydrolysis can be carried out in accordance with, for example, the
method described in "Experimental Chemistry Course, Fifth Edition",
Maruzen Co., Ltd., edited by The Chemical Society of Japan, Vol.
16, pp. 10-15.
[0199] In the present invention, the metal complex dye of the
present invention can be synthesized using the ligand LA
synthesized by the hydrolysis of the precursor compound. Further,
the metal complex dye of the present invention can also be
synthesized by forming a metal complex dye using a precursor
compound, and then hydrolyzing an ester group in accordance with
the above method, as in Example 1 which will be described
later.
##STR00015##
[0200] In the formula, L.sup.V represents the amino
group-containing heteroaryl group
(Het.sup.1-(Ar.sup.1)m-NR.sup.1R.sup.2). In Formula (L1-1),
Y.sup.L1 represents a trialkyl tin group, a boronic acid group, a
boronic acid ester group, a halogen atom, or a
perfluoroalkylsulfonyloxy group.
[0201] In Formula (L1-2), in a case where Y.sup.L1 of Formula
(L1-1) is a trialkyl tin group, a boronic acid group, or a boronic
acid ester group, Y.sup.L2 represents a halogen atom or a
perfluoroalkylsulfonyloxy group, and in a case where Y.sup.L1 of
Formula (L1-1) is a halogen atom or a perfluoroalkylsulfonyloxy
group, Y.sup.L2 represents a trialkyl tin group, a boronic acid
group, or a boronic acid ester group.
[0202] In Formulae (L1-2) and (L1-3), R represents an alkyl group,
an aryl group, or a heteroaryl group.
[0203] Specific examples of the ligand LA are shown below. Examples
of the ligand LA also include the ligand LA in the metal complex
dye which will be described later. Other examples thereof include
the compounds in which at least one of --COOH's is formed into a
salt of a carboxyl group, with respect to the ligands LA in the
following specific examples and the specific examples of the metal
complex dye. In these compounds, examples of the counter cation
that forms a salt of a carboxyl group include the positive ions
described as CI below. Further, examples of the esterified product
of the terpyridine compound include the compounds in which at least
one of acidic groups is esterified, with respect to the ligands LA
in the following specific examples and the specific examples of the
metal complex dye. The present invention is not limited to these
ligands LA, or salts or esterified products thereof. In the
following specific examples, Me represents methyl.
##STR00016## ##STR00017## ##STR00018## ##STR00019## ##STR00020##
##STR00021## ##STR00022## ##STR00023## ##STR00024## ##STR00025##
##STR00026## ##STR00027## ##STR00028##
[0204] --Ligand LD--
[0205] LD is a bidentate ligand, or a tridentate ligand different
from the ligand LA.
[0206] It is preferable that this ligand LD does not have an acidic
group adsorbed on the surface of semiconductor fine particles. Even
when the ligand LD includes a group corresponding to the acidic
group, it is preferable that the group is not adsorbed on the
surface of semiconductor fine particles.
[0207] In the ligand LD, it is preferable that at least one of
coordinating atoms bonded to the metal ion M is an anion. The
expression, "being an anion", means that a hydrogen atom in a
molecule or a hydrogen atom bonded to a coordinating atom can be
dissociated and bonded to the metal ion M. If the metal complex dye
has the ligand LD coordinating to the metal ion M through an anion
of a coordinating atom, together with the ligand LA, the heat
stability of the photoelectric conversion element or the
dye-sensitized solar cell is enhanced, and particularly high
durability as well as high photoelectric conversion efficiency are
exhibited.
[0208] The ligand LD is not particularly limited as long as it is a
bidentate or tridentate ligand.
[0209] Examples thereof include a ligand which coordinates with a
group selected from the group consisting of an acyloxy group, an
acylthio group, a thioacyloxy group, a thioacylthio group, an
acylaminooxy group, a thiocarbamate group, a dithiocarbamate group,
a thiocarbonate group, a dithiocarbonate group, a trithiocarbonate
group, an acyl group, an alkylthio group, an arylthio group, an
alkoxy group, and an aryloxy group, for example, a ligand which
coordinates with a group formed by the mutual linking of 2 or 3
groups selected from the above group.
[0210] Other examples thereof include ligands such as 1,3-diketone,
carbonamide, thiocarbonamide, thiourea, and quinolinol. The
1,3-diketone is not particularly limited, and preferred examples
thereof include 1,3-diketone having 3 to 20 carbon atoms, for
example acetylacetone, trifluoroacetylacetone,
trifluoroacetyltrifluoroacetone, 4-fluorobenzoyltrifluoroacetone,
dipivaloylmethane, dibenzoylmethane, and 3-chloroacetylacetone.
[0211] Moreover, a ligand represented by the following Formula (DL)
can also be included.
[0212] Among the ligands, a ligand represented by the following
Formula (DL) is preferable.
##STR00029##
[0213] In the formula, the ring D.sup.DL, the ring E.sup.DL, and
the ring F each independently represent an aromatic ring as a 5- or
6-membered ring. R.sup.a, R.sup.a1, and R.sup.a4 each independently
represent a substituent not having an acidic group. mb represents 0
or 1.
[0214] ma1 and ma4 each independently represent an integer of 0 to
3. When mb is 0, ma represents an integer of 0 to 4, and when mb is
1, ma represents an integer of 0 to 3.
[0215] Here, when ma, ma1, and ma4 are each an integer of 2 or
more, a plurality of R.sup.a's, a plurality of R.sup.a1's, and a
plurality of R.sup.a4's may be the same as or different from each
other, and they may be bonded to each other to form a ring.
Further, R.sup.a and R.sup.a1, and R.sup.a and R.sup.a4 may be
linked to each other to form a ring.
[0216] Examples of the aromatic ring as a 5- or 6-membered ring in
the ring D.sup.DL, the ring E.sup.DL and the ring F include an
aromatic hydrocarbon ring and an aromatic hetero ring, with an
aromatic hetero ring being preferable. Further, the respective
rings of the ring D.sup.DL, the ring E.sup.DL, and the ring F may
be fused with at least one of an aromatic ring and an aliphatic
hydrocarbon ring.
[0217] In a case where the ring D.sup.DL, the ring E.sup.DL, and
the ring F are each an aromatic hydrocarbon ring, a benzene ring is
preferable.
[0218] The aromatic hetero ring may be any of aromatic rings
including the heteroatom as a ring-constituting atom, and is
preferably, for examples, a non-fused 6-membered ring, a 6-membered
ring fused with a 5-membered ring, a 5-membered ring fused with a
benzene ring, or a 6-membered ring fused with a benzene ring, more
preferably a non-fused 6-membered ring or a 6-membered ring fused
with a 5-membered ring, and still more preferably a non-fused
6-membered ring.
[0219] Examples of such an aromatic hetero ring include, as a
6-membered ring, a pyridine ring, a pyrimidine ring, a pyrazine
ring, a triazine ring, a quinoline ring, and a quinazoline ring;
and as a 5-membered ring, a pyrrole ring, an imidazole ring, a
pyrazole ring, an oxazole ring, a thiazole ring, a benzimidazole
ring, a benzoxazole ring, a benzothiazole ring, an indole ring, an
indazole ring, a triazole ring, a thiophene ring, and a furan
ring.
[0220] The ring D.sup.DL and the ring E.sup.DL are each preferably
a pyrrole ring, a pyrazole ring, an imidazole ring, a triazole
ring, or a benzene ring, and more preferably a pyrazole ring, a
triazole ring, or a benzene ring.
[0221] The ring F is preferably a nitrogen atom-containing aromatic
hetero ring, more preferably a pyridine ring, a pyrimidine ring, a
pyrazine ring, or a triazine ring, still more preferably a pyridine
ring or a pyrimidine ring, and particularly preferably a pyridine
ring.
[0222] Here, the ring D.sup.DL, the ring E.sup.DL, and the ring F
each include a coordinating atom bonded to the metal ion M. The
coordinating atom is not particularly limited, but is preferably a
carbon atom, a nitrogen atom, a sulfur atom, an oxygen atom, or an
anion of any of these atoms.
[0223] The anion bonded to the metal ion M is not particularly
limited, and preferred examples thereof include carbon anions such
as a .dbd.C.sup.--- ion, and nitrogen anions such as > N.sup.-
ion.
[0224] Examples of the substituents of R.sup.a, R.sup.a1, and
R.sup.a4 include a group selected from the substituent group T
which will be described later.
[0225] Among those, R.sup.a is preferably an aromatic hetero ring
group, an aromatic hydrocarbon ring group, an ethenyl group, an
ethynyl group, a halogen atom, an alkyl group, an amino group
(including an alkylamino group, a dialkylamino group, an arylamino
group, a diarylamino group, an N-alkyl-N-arylamino group, and the
like), an alkoxy group, an aryloxy group, an alkylthio group, an
arylthio group, or a silyl group, and more preferably an aromatic
hetero ring group, an aromatic hydrocarbon ring group, an ethenyl
group, an ethynyl group, an alkyl group, an alkoxy group, or an
amino group (including an alkylamino group, a dialkylamino group,
an arylamino group, a diarylamino group, and the like). Further, a
group formed by the combination of the respective groups is also
preferable.
[0226] As each of R.sup.a1 and R.sup.a4, an alkyl group, a
cycloalkyl group, an alkenyl group (preferably an ethenyl group),
an alkynyl group (preferably an ethynyl group), an aryl group, a
hetero ring group (preferably an aromatic hetero ring group), a
halogen atom, an alkoxy group, an alkoxycarbonyl group, a
cycloalkoxycarbonyl group, an aryloxy group, an alkylthio group, an
arylthio group, an amino group, a cyano group, an alkylsulfonyl
group, an arylsulfonyl group, a halogenated alkyl group (for
example, a fluoroalkyl group), or a halogenated aryl group is
preferable; a halogenated alkyl group, a halogenated aryl group, a
halogen atom, a cyano group, an alkylsulfonyl group, or an
arylsulfonyl group is more preferable; and a halogenated alkyl
group, a halogenated aryl group, a halogen atom, or a cyano group
is still more preferable. Further, a group formed by the
combination of the respective groups is also preferable.
[0227] The number of carbon atoms in the respective substituents
which can be adopted as R.sup.a is not particularly limited, but is
preferably the same as the number of carbon atoms in the
substituent which can be adopted as R.sup.AA, with respect to the
same substituent as the substituent which can be adopted as
R.sup.AA, which will be described later, among the respective
substituents which can be adopted as R.sup.a, and more preferably,
a preferred range of the number of carbon atoms is the same as that
of the substituent which can be adopted as R.sup.AA. The number of
carbon atoms is the same as the number of carbon atoms in the
respective substituents of the substituent group T which will be
described later, and a preferred range thereof is also the same,
with respect to a substituent other than the substituent which can
be adopted as R.sup.AA, which will be described later, among the
respective substituents which can be adopted as R.sup.a. This also
applies to the respective substituents which can be adopted as
R.sup.a1 or R.sup.a4.
[0228] In a case where R.sup.a, R.sup.a1, or R.sup.a4 has a group
formed by further combination of a plurality of the respective
groups as a substituent, it is preferable that R.sup.a, R.sup.a1,
and R.sup.a4 each have a group R.sup.VU represented by the
following Formula (V.sup.U-1) or (V.sup.U-2) as a substituent, and
it is particularly preferable that R.sup.a has the following group
R.sup.VU.
##STR00030##
[0229] In Formula (V.sup.U-1), T represents an oxygen atom, a
sulfur atom, --NR.sup.CA--, --C(R.sup.CA).sub.2--, or
--Si(R.sup.CA).sub.2--, and R.sup.CA's each represent a hydrogen
atom or a substituent. R.sup.AA, R.sup.AB, and R.sup.AC each
independently represent a hydrogen atom or a substituent, and at
least one of R.sup.AA, . . . , or R.sup.AC represents a
substituent. It is preferable that at least one of R.sup.AA, . . .
, or R.sup.AC is a substituent, and it is more preferable that
R.sup.AA is a substituent, and R.sup.AB and R.sup.AC are each a
hydrogen atom or a substituent.
[0230] In Formula (V.sup.U-2), R.sup.BA to R.sup.BE each
independently represent a hydrogen atom or a substituent, and at
least one of R.sup.BA, R.sup.BB, R.sup.BD, or R.sup.BE represents a
substituent.
[0231] The number of the groups R.sup.VU contained in the ligand LD
may be any number of 1 or more, and is preferably 1 to 3, and more
preferably 1 or 2.
[0232] In Formula (V.sup.U-1), T is an oxygen atom, a sulfur atom,
--NR.sup.CA--, --C(R.sup.CA).sub.2--, or --Si(R.sup.CA).sub.2--,
with a sulfur atom being preferable. Here, R.sup.CA's each
represent a hydrogen atom or a substituent, with a hydrogen atom
being preferable. Examples of the substituent which can be adopted
as R.sup.CA include a group selected from the substituent group T
which will be described later.
[0233] R.sup.AA preferably represents a substituent. The
substituent which can be adopted as R.sup.AA is not particularly
limited, and examples thereof include a group selected from the
substituent group T which will be described later. The substituent
is preferably an alkyl group, a cycloalkyl group, an alkoxy group,
a cycloalkoxy group, an aryloxy group, an alkylthio group, a
cycloalkylthio group, an arylthio group, an amino group, an
alkylamino group, a cycloalkylamino group, an arylamino group, a
hetero ring amino group, a silyl group, or a silyloxy group.
[0234] Among the respective groups, the substituent which can be
adopted as R.sup.AA is more preferably an alkyl group, a cycloalkyl
group, an alkoxy group, a cycloalkoxy group, an alkylthio group, a
cycloalkylthio group, an amino group, an alkylamino group, a
cycloalkylamino group, or an arylamino group, still more preferably
an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy
group, an alkylamino group, a cycloalkylamino group, or an
arylamino group, particularly preferably an alkyl group, an alkoxy
group, or an alkylamino group, and most preferably an alkyl group
or an alkoxy group.
[0235] The substituent which can be adopted as R.sup.AA is
preferably bonded to a thiophene ring (in a case where T is a
sulfur atom) in view of photoelectric conversion efficiency.
[0236] The substituent which can be adopted as R.sup.AA may further
be substituted with a group selected from the substituent group T
which will be described later.
[0237] The alkyl group encompasses a linear alkyl group and a
branched alkyl group. The number of carbon atoms in the alkyl group
is preferably 1 to 30, more preferably 4 to 30, still more
preferably 5 to 26, and particularly preferably 6 to 20. Examples
of the alkyl group include methyl, ethyl, n-butyl, t-butyl,
n-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-decyl,
3,7-dimethyloctyl, isodecyl, s-decyl, n-dodecyl, 2-butyloctyl,
n-hexadecyl, isohexadecyl, n-eicosy, n-hexacosyl, isooctacosyl,
trifluoromethyl, and pentafluoroethyl.
[0238] The number of carbon atoms in the cycloalkyl group is
preferably 3 to 30, more preferably 5 to 30, still more preferably
6 to 26, and particularly preferably 6 to 20. Examples of the
cycloalkyl group include cyclopropyl, cyclopentyl, cyclohexyl,
cycloheptyl, and cyclooctyl. The cycloalkyl group may also be fused
with an aliphatic ring, an aromatic ring, or a hetero ring.
[0239] The alkoxy group encompasses a linear alkoxy group and a
branched alkoxy group. The alkyl moiety of the alkoxy group has the
same definition as the alkyl group, and preferred examples thereof
are also the same. Examples of the alkoxy group include methoxy,
ethoxy, n-propoxy, i-propoxy, n-butoxy, t-butoxy, n-pentoxy,
n-hexyloxy, n-octyloxy, 2-ethylhexyloxy, 3,7-dimethyloctyloxy,
n-decyloxy, isodecyloxy, s-decyloxy, 2-butyloctyloxy, n-dodecyloxy,
n-hexadecyloxy, isohexadecyloxy, n-eicosyoxy, n-hexacosyloxy, and
isooctacosyloxy.
[0240] The cycloalkyl moiety of the cycloalkoxy group has the same
definition as the cycloalkyl group, and preferred examples thereof
are also the same. Examples of the cycloalkoxy group include
cyclopropyloxy, cyclopentyloxy, cyclohexyloxy, cycloheptyloxy, and
cyclooctyloxy.
[0241] The aryloxy group encompasses a carbocyclic aryloxy group in
which an aryl group is an aromatic carbon-based ring group
(aromatic hydrocarbon ring group), and a heteroaryloxy group in
which an aryl group is an aromatic hetero ring group. The number of
carbon atoms in the aryloxy group is preferably 3 to 30, more
preferably 3 to 25, still more preferably 3 to 20, and particularly
preferably 3 to 16. Examples of the aryloxy group include phenoxy,
naphthoxy, imidazoyloxy, benzimidazoyloxy, pyridin-4-yloxy,
pyrimidinyloxy, quinazolinyloxy, purinyloxy, and thiophen-3-yloxy.
As the hetero ring of the heteroaryloxy group, a thiophene ring is
preferable.
[0242] The alkylthio group encompasses a linear alkylthio group and
a branched alkylthio group. The alkyl moiety of the alkylthio group
has the same definition as the alkyl group, and preferred examples
thereof are also the same. Examples of the alkylthio group include
methylthio, ethylthio, n-propylthio, i-propylthio, n-butylthio,
t-butylthio, n-pentylthio, n-hexylthio, n-octylthio,
2-ethylhexylthio, 3,7-dimethyloctylthio, n-decylthio, isodecylthio,
s-decylthio, n-dodecylthio, 2-butyloctylthio, n-hexadecylthio,
isohexadecylthio, n-eicosythio, n-hexacosylthio, and
isooctacosylthio.
[0243] The cycloalkyl moiety of the cycloalkylthio group has the
same definition as the cycloalkyl group, and preferred examples
thereof are also the same. Examples of the cycloalkylthio group
include cyclopropylthio, cyclopentylthio, cyclohexylthio,
cycloheptylthio, and cyclooctylthio.
[0244] The arylthio group encompasses a carbocyclic arylthio group
in which an aryl group is an aromatic carbon-based ring, and a
heteroarylthio group in which an aryl group is an aromatic hetero
ring group. The number of carbon atoms in the arylthio group is
preferably 3 to 30, more preferably 3 to 25, still more preferably
3 to 20, and particularly preferably 3 to 16. Examples of the
arylthio group include phenylthio, naphthylthio, imidazoylthio,
benzimidazoylthio, pyridin-4-ylthio, pyrimidinylthio,
quinazolinylthio, purinylthio, and thiophen-3-ylthio. As the hetero
ring of the heteroarylthio group, a thiophene ring is
preferable.
[0245] The alkylamino group encompasses an N-alkylamino group and
an N,N-dialkylamino group, and the number of carbon atoms in the
alkyl group is preferably 1 to 30, and more preferably 2 to 30.
Examples of the alkylamino group include ethylamino, diethylamino,
2-ethylhexylamino, bis(2-ethylhexyl)amino, and
n-octadecylamino.
[0246] The cycloalkylamino group encompasses an N-cycloalkylamino
group and an N,N-dicycloalkylamino group. The cycloalkyl moiety of
the cycloalkylamino group has the same definition as the cycloalkyl
group, and preferred examples thereof are also the same. Examples
of the cycloalkylamino group include cyclopropylamino,
dicyclopropylamino, N-cyclopropyl-N-ethylamino, cyclopentylamino,
dicyclopentylamino, N-cyclopentyl-N-methylamino, cyclohexylamino,
dicyclohexylamino, cycloheptylamino, and cyclooctylamino.
[0247] The arylamino group encompasses a carbocyclic arylamino
group in which an aryl group is an aromatic carbon-based ring, and
a heteroarylamino group in which an aryl group is an aromatic
hetero ring group. Further, the carbocyclic arylamino group
encompasses an N-arylamino group, an N-alkyl-N-arylamino group, and
an N,N-diarylamino group. The heteroarylamino group encompasses an
N-heteroarylamino group, an N-alkyl-N-heteroarylamino group, an
N-aryl-N-heteroarylamino group, and an N,N-diheteroarylamino
group.
[0248] The number of carbon atoms in the arylamino group is
preferably 3 to 30, more preferably 3 to 25, still more preferably
3 to 20, and particularly preferably 3 to 16. Examples of the
arylamino group include phenylamino, N-phenyl-N-ethylamino,
naphthylamino, imidazoylamino, benzimidazoylamino,
pyridin-4-ylamino, pyrimidinylamino, quinazolinylamino,
purinylamino, and thiophen-3-ylamino.
[0249] The heterocyclic amino group is a heterocyclic amino group
(aliphatic heterocyclic amino group) other than a heteroarylamino
group. The number of carbon atoms is preferably 0 to 30, more
preferably 1 to 25, still more preferably 2 to 20, and particularly
preferably 2 to 16. Further, in the hetero ring, the
ring-constituting heteroatom is preferably selected from an oxygen
atom, a sulfur atom, and a nitrogen atom, and in terms of the
number of ring members, 5- to 7-membered rings are preferable, and
5- or 6-membered rings are more preferable. Examples of the
heterocyclic amino group include pyrrolidin-3-ylamino,
imidazolidinylamino, benzimidazolidinylamino, piperidin-4-ylamino,
and tetrahydrothiophen-3-ylamino.
[0250] The silyl group encompasses an alkylsilyl group, a
cycloalkylsilyl group, an arylsilyl group, an alkyloxysilyl group,
a cycloalkyloxysilyl group, and an aryloxysilyl group. The silyl
group is preferably an alkylsilyl group, a cycloalkylsilyl group,
or an arylsilyl group. The number of carbon atoms in the silyl
group is preferably 3 to 30, more preferably 3 to 24, still more
preferably 3 to 20, and particularly preferably 3 to 18. Examples
of the silyl group include trimethylsilyl, triethylsilyl,
t-butyldimethylsilyl, cyclohexyldimethylsilyl, triisopropylsilyl,
t-butyldiphenylsilyl, methyldimethoxysilyl, phenyldimethoxysilyl,
and phenoxydimethylsilyl.
[0251] The silyloxy group encompasses an alkylsilyloxy group, a
cycloalkylsilyloxy group, and an arylsilyloxy group. The number of
carbon atoms in the silyloxy group is preferably 3 to 30, more
preferably 3 to 24, still more preferably 3 to 20, and particularly
preferably 3 to 18. Examples of the silyloxy group include
trimethylsilyloxy, triethylsilyloxy, t-butyldimethylsilyloxy,
triisopropylsilyloxy, cyclohexyldimethylsilyloxy, and
t-butyldiphenylsilyloxy.
[0252] R.sup.AB represents a hydrogen atom or a substituent, with a
hydrogen atom being preferable.
[0253] R.sup.AC represents a hydrogen atom or a substituent.
[0254] The substituent which can be adopted as R.sup.AB and
R.sup.AC has the same definition as R.sup.AA and preferred examples
thereof are also the same. In a case where R.sup.AB or R.sup.AC is
a substituent, the substituent may be the same as or different from
R.sup.AA
[0255] In the group R.sup.vu represented by Formula (V.sup.U-2),
R.sup.BA to R.sup.BE each independently represent a hydrogen atom
or a substituent. The substituent which can be adopted as each of
R.sup.BA to R.sup.BE has the same definition as R.sup.AA, and
preferred examples thereof are also the same. Here, at least one of
R.sup.BA, R.sup.BB, R.sup.BD, or R.sup.BE is a substituent. It is
particularly preferable that at least one or both of R.sup.BA and
R.sup.BE are a substituent, and all of R.sup.BB, R.sup.BC, and
R.sup.BD are a hydrogen atom; or at least one or both of R.sup.BB
and R.sup.BD are a substituent, and all of R.sup.BA, R.sup.BC, and
R.sup.BE are a hydrogen atom.
[0256] In a case where two or more members out of R.sup.BA to
R.sup.BE are substituents, two or more substituents may be the same
as or different from each other.
[0257] In Formula (DL), ma, ma1, and ma4 are each preferably an
integer of 0 to 2, and more preferably 1 or 2.
[0258] In a case where the ring F has R.sup.a, the position
(substitution position) at which R.sup.a is bonded in the ring F is
not particularly limited. In a case where the ring F is a
5-membered ring, the 3-position with respect to a ring-constituting
nitrogen atom coordinating to the metal atom M is preferable. In a
case where the ring F is a 6-membered ring, the 3- or 4-position is
preferable, and the 4-position is more preferable, with respect to
a ring-constituting nitrogen atom coordinating to the metal atom
M.
[0259] Furthermore, in a case where the ring D.sup.DL and the ring
E.sup.DL each have R.sup.a1 or R.sup.a4, the position at which
R.sup.a1 or R.sup.a4, in each of the ring D.sup.DL and the ring
E.sup.DL, is bonded is not particularly limited.
[0260] The ligand represented by Formula (DL) is preferably
represented by the following Formula (DL-1) or (DL-2).
##STR00031##
[0261] R.sup.a2 and R.sup.a3 each independently represent a
substituent not having an acidic group. ma2 represents 0 or 1, with
1 being preferable. ma3 represents an integer of 0 to 2, with 1 or
2 being more preferable.
[0262] X1 and X2 each independently represent CR.sup.a5 or a
nitrogen atom. R.sup.a5 represents a hydrogen atom or a
substituent. This substituent has the same definition as R.sup.a in
Formula (DL), and a preferred range thereof is also the same. A
ring including X1 and X2 (also referred to as a ring F) has the
same definition as the ring F in Formula (DL), and a preferred
range thereof is also the same.
[0263] R.sup.a1, R.sup.a4, ma1, and ma4 have the same definitions
as R.sup.a1, R.sup.a4, ma1, and ma4, respectively, in Formula (DL),
and preferred ranges thereof are also the same.
[0264] The substituents represented by R.sup.a2 and R.sup.a3 have
the same definitions as R.sup.a in Formula (DL), and preferred
ranges thereof are also the same.
[0265] When ma1, ma3, and ma4 are each an integer of 2 or more, a
plurality of R.sup.a1's, R.sup.a3's, and R.sup.a4's each may be the
same as or different from each other, and may be bonded to each
other to form a ring.
[0266] The ring D and the ring E each independently represent an
aromatic ring as a 5- or 6-membered ring. Examples of such an
aromatic ring include the rings mentioned as the ring D.sup.DL and
the ring E.sup.DL in Formula (DL), and preferred aromatic rings are
also the same as the rings mentioned as the ring D.sup.DL and the
ring E.sup.DL
[0267] Furthermore, the bond between D.sup.1 and D.sup.2 in the
ring D and the ring E, and a carbon atom bonded to the ring F may
be a single bond or a double bond.
[0268] D.sup.1 and D.sup.2 each independently represent an anion of
a carbon atom or an anion of a nitrogen atom.
[0269] The ring D and the ring E are each preferably a pyrrole
ring, an imidazole ring, a pyrazole ring, a triazole ring, or a
benzene ring, with a pyrazole ring, a triazole ring, or a benzene
ring being more preferable.
[0270] In a case where the ligand LD is a bidentate ligand, a
bidentate ligand represented by any one of the following Formulae
(2L-1) to (2L-4) is preferable.
##STR00032##
[0271] In the formulae, * represents a binding position to a metal
ion M. The ring D.sup.2L represents an aromatic ring. A.sup.111 to
A.sup.141 each independently represent an anion of a nitrogen atom
or an anion of a carbon atom. R.sup.111 to R.sup.143 each
independently represent a hydrogen atom or a substituent not having
an acidic group.
[0272] Here, A.sup.111 to A.sup.141 are each an anion of a carbon
atom or an anion of a nitrogen atom, in which a hydrogen atom
bonded to a nitrogen atom or a carbon atom constituting the ring
D.sup.2L is dissociated. In Formulae (2L-1) to (2L-4), examples of
the ring D.sup.2L include an aromatic hydrocarbon ring, an
oxygen-containing aromatic hetero ring, a sulfur-containing
aromatic hetero ring, and a nitrogen-containing aromatic hetero
ring.
[0273] Examples of the aromatic hydrocarbon ring include a benzene
ring and a naphthalene ring, among which a benzene ring is
preferable, and a benzene ring substituted with a halogen atom, a
halogenated alkyl group, or a halogenated aryl group is more
preferable. The halogenated alkyl group is an alkyl group
substituted with a halogen atom, with a fluorinated alkyl group
(for example, a trifluoromethyl group) being preferable. As the
halogenated aryl group, a phenyl group substituted with 1 to 5
halogen atoms is preferable.
[0274] As the oxygen-containing aromatic hetero ring, a furan ring
is preferable, and as the sulfur-containing aromatic hetero ring, a
thiophene ring is preferable. As the nitrogen-containing aromatic
hetero ring, a pyrrole ring, a pyrazole ring, an imidazole ring, or
a triazole ring is preferable.
[0275] Preferred examples of the ring D.sup.2L include the
respective rings in which one of ring-constituting atoms of a
benzene ring, a thiophene ring, or a furan ring becomes an anion,
or the respective rings represented by the following Formulae (a-1)
to (a-5), (a-1a), (a-2a), (a-1b), and (a-4a).
##STR00033##
[0276] In the formula, Rd represents a substituent not having an
acidic group. b1 represents an integer of 0 to 2, b2 represents an
integer of 0 to 3, and b3 represents 0 or 1. When b1 is 2 or when
b2 is 2 or more, the plurality of Rd's may be the same as or
different from each other. Further, a plurality of Rd's may be
bonded to each other to form a ring. Examples of Rd include a group
selected from the substituent group T which will be described
later.
##STR00034##
[0277] In the formulae, Rd, and b1 to b3 have the same definitions
as Rd, and b1 to b3, respectively, in Formula (a-1) to (a-5), and
preferred ranges thereof are also the same. b4 represents an
integer of 0 to 4, and b5 represents an integer of 0 to 5. In
Formulae (a-1a) and (a-1b), Rd also represents the group which may
also be contained in a pyrrole ring, in addition to a benzene
ring.
[0278] Rd is preferably a linear or branched alkyl group, a
cycloalkyl group, an alkenyl group, a fluoroalkyl group, an aryl
group, a halogen atom, an alkoxycarbonyl group, a
cycloalkoxycarbonyl group, a cyano group, an alkylsulfonyl group,
an arylsulfonyl group, or a group formed by the combination of
these groups, more preferably a linear or branched alkyl group, a
cycloalkyl group, an alkenylnyl group, an aryl group, or a group
formed by the combination of these groups, and still more
preferably a linear or branched halogenated alkyl group or a
halogenated aryl group.
[0279] The substituents represented by R.sup.111 to R.sup.143 have
the same definitions as R.sup.a in Formula (DL), and preferred
ranges thereof are also the same.
[0280] Preferably at least one, and more preferably one or two of
R.sup.111 to R.sup.114, R.sup.121 to R.sup.123, R.sup.131 to
R.sup.133, and R.sup.141 to R.sup.143, respectively, are
substituents.
[0281] In a case where the ligand LD is tridentate ligand, it is
preferably a tridentate ligand represented by any one of the
following Formulae (3L-1) to (3L-4).
##STR00035##
[0282] In the formulae, * represents a binding position to a metal
ion M. The ring D.sup.2L represents an aromatic ring. A.sup.211 to
A.sup.242 each independently represent a nitrogen atom or a carbon
atom, in which at least one of A.sup.211 and A.sup.212, A.sup.221
and A.sup.222, A.sup.231 and A.sup.232, and A.sup.241 and
A.sup.242, respectively, is an anion. R.sup.211 to R.sup.241 each
independently represent a hydrogen atom, or a substituent not
having an acidic group.
[0283] A.sup.211 to A.sup.242 which are anions have the same
definitions as A.sup.111 to A.sup.141, respectively, in Formulae
(2L-1) to (2L-4). A.sup.211 to A.sup.242, which do not have an
anion, are each a nitrogen atom not having a hydrogen atom.
[0284] The ring D.sup.2L in Formulae (3L-1) to (3L-4) has the same
definition as the ring D.sup.2L in Formulae (2L-1) to (2L-4), and a
preferred range thereof is also the same. The ring D.sup.2L is more
preferably an aromatic ring including any one of A.sup.211 to
A.sup.242 and a carbon atom or an aromatic ring including two
carbon atoms. Here, two ring D.sup.2L's in the respective formulae
may be the same as or different from each other.
[0285] The substituents R.sup.211 to R.sup.241 have the same
definitions as R.sup.a in Formula (DL), and preferred examples
thereof are also the same.
[0286] In the present invention, the bidentate or tridentate ligand
in the ligand LD, in which the atom coordinating to the metal ion M
is a nitrogen anion or a carbon anion, and an arylamino group or a
diarylamino group is contained in the substituent, is preferable,
in particular, due to absorption at a longer wavelength.
[0287] Specifically, the preferred ligand is the ligand in which at
least one of the atoms coordinating to the metal ion M is a
nitrogen anion or a carbon anion, and the ligand has the following
Formula (SA) as a partial structure.
##STR00036##
[0288] In the formula, R.sup.DA1 represents an aryl group, and
R.sup.DA2 represents an alkyl group or an aryl group. R.sup.DA1 and
R.sup.DA2 may be bonded to each other to form a ring. LL represents
an ethenyl group, an ethynyl group, an arylene group, or a
heteroarylene group. a represents an integer of 0 to 5, and when a
is 2 or more, LL's present in plural numbers may be the same as or
different from each other.
[0289] The group represented by Formula (SA) is preferably
substituted with an aromatic hydrocarbon ring coordinating to the
metal ion M or a nitrogen-containing aromatic hetero ring, and more
preferably substituted with a nitrogen atom-containing aromatic
hetero ring.
[0290] In the group represented by Formula (SA), it is preferable
that at least one of R.sup.DA1 or R.sup.DA2 is an aryl group or a
heteroaryl group. The aryl group or the heteroaryl group may have a
substituent, and examples of such a substituent include a group
selected from the substituent group T which will be described
later.
[0291] The aryl group is not particularly limited, and examples
thereof include a phenyl group and a naphthyl group, with a phenyl
group being preferable. The heteroaryl group is not particularly
limited, but is preferably a furanyl group or a thienyl group.
[0292] LL may form a fused structure together with an aromatic
hydrocarbon ring including a coordinating atom of the ligand or a
nitrogen-containing aromatic hetero ring. For example, LL may be an
ethenyl group, and this ethenyl group may be bonded to a
nitrogen-containing aromatic hetero ring including a coordinating
atom of the ligand to form a quinoline ring.
[0293] Examples of the arylene group in LL include a phenylene
group and a naphthylene group, and the heteroarylene group is
preferably a divalent 5- or 6-membered ring which contains an
oxygen atom, a sulfur atom, or a nitrogen atom as a
ring-constituting atom, and may be fused with a benzene ring or a
hetero ring.
[0294] Examples of the hetero ring of the heteroarylene group
include a furan ring, a thiophene ring, a pyrrole ring, and a
pyridine ring, with a furan ring or a thiophene ring being
preferable.
[0295] The ethenyl group, the arylene group, or the heteroarylene
group in LL may have a substituent, and examples of the substituent
include a group selected from the substituent group T which will be
described later.
[0296] In Formula (SA), it is preferable that a is 0, or that a is
1 and LL is an ethenyl group, an ethynyl group, a phenylene group,
or a heteroarylene group; it is more preferable that a is 0, or
that a is 1 and LL is a phenylene group or a heteroarylene group;
it is still more preferable that a is 0, or that a is 1 and LL is a
phenylene group, a divalent furan ring group, or a divalent
thiophene ring group; and it is particularly preferable that a is
0.
[0297] In the present invention, it is also preferable that
R.sup.DA1 and R.sup.DA2 are bonded to each other to form a
ring.
[0298] The ring thus formed is preferably a 5- or 6-membered ring,
and more preferably a ring formed by the bonding of R.sup.DA1 and
R.sup.DA2 which are both an aryl group.
[0299] The rings formed by the mutual bonding of R.sup.DA1 and
R.sup.DA2 are preferably the following rings.
##STR00037##
[0300] Here, R.sup.DA3 and R.sup.DA4 each independently represent
an alkyl group.
[0301] The ring may have a substituent, and examples of such a
substituent include a group selected from the substituent group T
which will be described later.
[0302] The ligand represented by Formula (DL) can be synthesized
by, for example, the method described in US2010/0258175A1,
JP4298799B, or Angew. Chem. Int. Ed., 2011, 50, pp. 2054-2058, the
methods described in the reference documents listed in these
documents, or the methods equivalent thereto.
[0303] Specific examples of the ligand represented by Formula (DL)
are shown below. Further, examples of the ligand LD also include
the ligand LD in the metal complex dye which will be described
later. The present invention is not limited to these ligands LD. In
the following specific examples, Me represents methyl, and *
represents a binding position at which rings are bonded to each
other, or a pyridine ring and the substituent R.sup.201 are bonded
to each other.
TABLE-US-00001 ##STR00038## LD No. Ring D Ring F Ring E LD-3-1
##STR00039## ##STR00040## ##STR00041## LD-3-2 ##STR00042##
##STR00043## ##STR00044## LD-3-3 ##STR00045## ##STR00046##
##STR00047## LD-3-4 ##STR00048## ##STR00049## ##STR00050## LD-3-5
##STR00051## ##STR00052## ##STR00053## LD-3-6 ##STR00054##
##STR00055## ##STR00056## LD-3-7 ##STR00057## ##STR00058##
##STR00059## LD-3-8 ##STR00060## ##STR00061## ##STR00062## LD-3-9
##STR00063## ##STR00064## ##STR00065## LD-3-10 ##STR00066##
##STR00067## ##STR00068## LD-3-11 ##STR00069## ##STR00070##
##STR00071## LD-3-12 ##STR00072## ##STR00073## ##STR00074## LD-3-13
##STR00075## ##STR00076## ##STR00077## LD-3-14 ##STR00078##
##STR00079## ##STR00080## LD-3-15 ##STR00081## ##STR00082##
##STR00083## LD-3-16 ##STR00084## ##STR00085## ##STR00086## LD-3-17
##STR00087## ##STR00088## ##STR00089## LD-3-18 ##STR00090##
##STR00091## ##STR00092## LD-3-19 ##STR00093## ##STR00094##
##STR00095## LD-3-20 ##STR00096## ##STR00097## ##STR00098## LD-3-21
##STR00099## ##STR00100## ##STR00101## LD-3-22 ##STR00102##
##STR00103## ##STR00104## LD-3-23 ##STR00105## ##STR00106##
##STR00107## LD-3-24 ##STR00108## ##STR00109## ##STR00110## LD-3-25
##STR00111## ##STR00112## ##STR00113## ##STR00114## LD No R203 R201
R202 LD-2-1 ##STR00115## H ##STR00116## LD-2-2 ##STR00117##
##STR00118## ##STR00119## LD-2-3 ##STR00120## ##STR00121##
##STR00122## LD-2-4 ##STR00123## ##STR00124## ##STR00125## LD-2-5
##STR00126## ##STR00127## ##STR00128## LD-2-6 ##STR00129##
##STR00130## ##STR00131## LD-2-7 ##STR00132## ##STR00133##
##STR00134## LD-2-8 ##STR00135## ##STR00136## ##STR00137## LD-2-9
##STR00138## ##STR00139## ##STR00140## LD-2-10 ##STR00141##
##STR00142## ##STR00143## LD-2-11 ##STR00144## ##STR00145##
##STR00146## LD-2-12 ##STR00147## ##STR00148## ##STR00149##
##STR00150## LD No Ring D Ring F LD-6-1 ##STR00151## ##STR00152##
LD-6-2 ##STR00153## ##STR00154## LD-6-3 ##STR00155## ##STR00156##
LD-6-4 ##STR00157## ##STR00158## LD-6-5 ##STR00159## ##STR00160##
LD-6-6 ##STR00161## ##STR00162## LD-6-7 ##STR00163## ##STR00164##
LD-6-8 ##STR00165## ##STR00166## LD-6-9 ##STR00167## ##STR00168##
LD-6-10 ##STR00169## ##STR00170## LD-6-11 ##STR00171## ##STR00172##
LD-6-12 ##STR00173## ##STR00174## LD-6-13 ##STR00175## ##STR00176##
LD-6-14 ##STR00177## ##STR00178## LD-6-15 ##STR00179## ##STR00180##
LD-6-16 ##STR00181## ##STR00182## LD-6-17 ##STR00183## ##STR00184##
LD-6-18 ##STR00185## ##STR00186## LD-6-19 ##STR00187## ##STR00188##
LD-6-20 ##STR00189## ##STR00190## LD-6-21 ##STR00191## ##STR00192##
LD-6-22 ##STR00193## ##STR00194## LD-6-23 ##STR00195## ##STR00196##
LD-6-24 ##STR00197## ##STR00198## LD-6-25 ##STR00199## ##STR00200##
LD-6-26 ##STR00201## ##STR00202## LD-6-27 ##STR00203## ##STR00204##
LD-6-28 ##STR00205## ##STR00206## LD-6-29 ##STR00207## ##STR00208##
LD-6-30 ##STR00209## ##STR00210## LD-6-31 ##STR00211## ##STR00212##
LD-6-32 ##STR00213## ##STR00214## LD-6-33 ##STR00215## ##STR00216##
LD-6-34 ##STR00217## ##STR00218## LD-6-35 ##STR00219## ##STR00220##
LD-6-36 ##STR00221## ##STR00222## LD-6-37 ##STR00223## ##STR00224##
LD-6-38 ##STR00225## ##STR00226## LD-6-39 ##STR00227## ##STR00228##
LD-6-40 ##STR00229## ##STR00230## LD-6-41 ##STR00231## ##STR00232##
LD-6-42 ##STR00233## ##STR00234## LD-6-43 ##STR00235## ##STR00236##
LD-6-44 ##STR00237## ##STR00238## LD-6-45 ##STR00239## ##STR00240##
LD-6-46 ##STR00241## ##STR00242## LD-6-47 ##STR00243## ##STR00244##
LD-6-48 ##STR00245## ##STR00246## LD-6-49 ##STR00247## ##STR00248##
LD-6-50 ##STR00249## ##STR00250## LD-6-51 ##STR00251## ##STR00252##
LD-6-52 ##STR00253## ##STR00254## LD-6-53 ##STR00255## ##STR00256##
LD-6-54 ##STR00257## ##STR00258## LD-6-55 ##STR00259## ##STR00260##
LD-6-56 ##STR00261## ##STR00262## LD-6-57 ##STR00263## ##STR00264##
LD-6-58 ##STR00265## ##STR00266## LD-6-59 ##STR00267## ##STR00268##
LD-6-60 ##STR00269## ##STR00270## LD-6-61 ##STR00271## ##STR00272##
LD-6-62 ##STR00273## ##STR00274## LD-6-63 ##STR00275## ##STR00276##
LD-6-64 ##STR00277## ##STR00278## LD-6-65 ##STR00279## ##STR00280##
LD-6-66 ##STR00281## ##STR00282## LD-6-67 ##STR00283## ##STR00284##
LD-6-68 ##STR00285## ##STR00286## LD-6-69 ##STR00287## ##STR00288##
LD-6-70 ##STR00289## ##STR00290## LD-6-71 ##STR00291## ##STR00292##
LD-6-72 ##STR00293## ##STR00294## LD-6-73 ##STR00295## ##STR00296##
LD-6-74 ##STR00297## ##STR00298## LD-6-75 ##STR00299## ##STR00300##
LD-6-76 ##STR00301## ##STR00302## LD-6-77 ##STR00303## ##STR00304##
LD-6-78 ##STR00305## ##STR00306## LD-6-79 ##STR00307## ##STR00308##
LD-6-80 ##STR00309## ##STR00310## LD-6-81 ##STR00311## ##STR00312##
LD-6-82 ##STR00313## ##STR00314##
LD-6-83 ##STR00315## ##STR00316## LD-6-84 ##STR00317## ##STR00318##
LD-6-85 ##STR00319## ##STR00320## LD-6-86 ##STR00321## ##STR00322##
LD-6-87 ##STR00323## ##STR00324## LD-6-88 ##STR00325## ##STR00326##
LD-6-89 ##STR00327## ##STR00328## LD-6-90 ##STR00329## ##STR00330##
LD-6-91 ##STR00331## ##STR00332## LD-6-92 ##STR00333## ##STR00334##
LD-6-93 ##STR00335## ##STR00336## LD-6-94 ##STR00337## ##STR00338##
LD-6-95 ##STR00339## ##STR00340## LD-6-96 ##STR00341## ##STR00342##
LD-6-97 ##STR00343## ##STR00344## LD-6-98 ##STR00345##
##STR00346##
[0304] --Ligand LX--
[0305] The ligand LX may be a monodentate ligand, and is
preferably, for example, a group or atom selected from the group
consisting of an acyloxy group, an acylthio group, a thioacyloxy
group, a thioacylthio group, an acylaminooxy group, a thiocarbamate
group, a dithiocarbamate group, a thiocarbonate group, a
dithiocarbonate group, a trithiocarbonate group, an acyl group, a
thiocyanate group, an isothiocyanate group, a cyanate group, an
isocyanate group, a cyano group, an alkylthio group, an arylthio
group, an alkoxy group, an aryloxy group, and a halogen atom, or
anions thereof.
[0306] In a case where the ligand LX includes an alkyl group, an
alkenyl group, an alkynyl group, an alkylene group, or the like,
these groups may or may not have a substituent. Further, in a case
where an aryl group, a hetero ring group, a cycloalkyl group, or
the like is included, these may or may not have a substituent, and
may be a monocycle or a fused ring.
[0307] Among those, the ligand LX is preferably a cyanate group, an
isocyanate group, a thiocyanate group, or an isothiocyanate group,
or an anion thereof, more preferably an isocyanate group (an
isocyanate anion) or an isothiocyanate group (an isothiocyanate
anion), and particularly preferably an isothiocyanate group (an
isothiocyanate anion).
[0308] --Counterion CI for Neutralizing Charge--
[0309] CI represents a counterion necessary for neutralizing the
charge of the metal complex dye. Generally, whether the metal
complex dye is cationic or anionic, or whether the metal complex
dye has a net ionic charge depends on the metal, the ligand, and
the substituent in the metal complex dye.
[0310] When the substituent has a dissociative group or the like,
the metal complex dye may have a negative charge arising from
dissociation. In this case, an electric charge of the metal complex
dye as a whole is electrically neutralized by CI.
[0311] In a case where the counterion CI is a positive counterion,
the counterion CI is, for example, an inorganic or organic ammonium
ion (for example, a tetraalkyl ammonium ion and a pyridinium ion),
a phosphonium ion (for example, a tetraalkylphosphonium ion and an
alkyltriphenylphosphonium ion), an alkali metal ion (a Li ion, a Na
ion, a K ion, and the like), an alkaline earth metal ion, a metal
complex ion, or a proton. As the positive counterion, an inorganic
or organic ammonium ion (a tetraethylammonium ion, a
tetrabutylammonium ion, a tetrahexylammonium ion, a
tetraoctylammonium ion, a tetradecylammonium ion, and the like), an
alkali metal ion, and a proton are preferable.
[0312] In a case where the counterion CI is a negative counterion,
the counterion CI is, for example, an inorganic anion or an organic
anion. Examples thereof include a hydroxide ion, a halogen anion
(for example, a fluoride ion, a chloride ion, a bromide ion, and an
iodide ion), a substituted or unsubstituted alkylcarboxylate ion
(for example, an acetate ion and a trifluoroacetate ion), a
substituted or unsubstituted arylcarboxylate ion (for example, a
benzoate ion), a substituted or unsubstituted alkylsulfonate ion
(for example, a methanesulfonate ion and a
trifluoromethanesulfonate ion), a substituted or unsubstituted
arylsulfonate ion (for example, a p-toluene sulfonate ion and a
p-chlorobenzene sulfonate ion), an aryldisulfonate ion (for
example, a 1,3-benzene disulfonate ion, a 1,5-naphthalene
disulfonate ion, and a 2,6-naphthalene disulfonate ion), an
alkylsulfate ion (for example, a methylsulfate ion), a sulfate ion,
a thiocyanate ion, a perchlorate ion, a tetrafluoroborate ion, a
hexafluorophosphate ion, and a picrate ion. Alternatively, as a
charge balance counterion, an ionic polymer or another dye with an
opposite charge from the dye in interest may be used, or a metal
complex ion (for example, a bisbenzene-1,2-dithiolatonickel (III))
may also be used. As the negative counterion, a halogen anion, a
substituted or unsubstituted alkylcarboxylate ion, a substituted or
unsubstituted alkylsulfonate ion, a substituted or unsubstituted
arylsulfonate ion, an aryldisulfonate ion, a perchlorate ion, and a
hexafluorophosphate ion are preferable, and a halogen anion and a
hexafluorophosphate ion are more preferable.
[0313] --Metal Complex Dye--
[0314] The metal complex dye of the present invention is
represented by Formula (I).
[0315] In the metal complex dye represented by Formula (I), the
ligand LA, the ligand LD, and the ligand LX are as described above,
and the combination of these ligands is not particularly limited. A
preferred combination of the ligands is a combination of the
preferred ligand LA, the preferred ligand LD, and the preferred
ligand LX.
M(LA)(LD).sub.p(LX).sub.q.(CI).sub.z Formula (I)
[0316] In the formula, M, LA, LD, p, LX, q, CI, and z are as
described above, and preferred examples thereof are also the
same.
[0317] The metal complex dye represented by Formula (I) is
preferably a metal complex dye represented by the following Formula
(I-1) or (I-2).
##STR00347##
[0318] In the formula, M and LX each have the same definitions as M
and LX in Formula (I).
[0319] Het.sup.1, Ar.sup.1, m, R.sup.1, and R.sup.2 each have the
same definitions as Het.sup.1, Ar.sup.1, m, R.sup.1, and R.sup.2 in
Formula (LA-1).
[0320] Anc's each independently represent an acidic group. The
acidic group has the same definition as the acidic group of Formula
(LA-1), and preferred examples thereof are also the same.
[0321] The ring D and the ring E each independently represent a 5-
or 6-membered aromatic ring. D.sup.1 and D.sup.2 each independently
represent an anion of a carbon atom or an anion of a nitrogen atom.
Here, the bond between D.sup.1 and D.sup.2 in the ring D and the
ring E and a carbon atom bonded to a pyridine ring is a single bond
or a double bond. The ring D and the ring E have the same
definitions as the ring D and the ring E of Formulae (DL-1) and
(DL-2), and preferred examples thereof are also the same.
[0322] R.sup.a1 to R.sup.a4 each independently represent a
substituent. R.sup.a1 to R.sup.a4 each have the same definitions as
R.sup.a1 to R.sup.a4 of Formulae (DL-1) and (DL-2), and preferred
examples thereof are also the same.
[0323] ma1, ma2, and ma4 each independently represent an integer of
0 to 3. ma3 represents an integer of 0 to 4. ma1 to ma4 each have
the same definitions as ma1 to ma4 of Formulae (DL-1) and (DL-2),
and preferred examples thereof are also the same. When mal to ma4
each represent an integer of 2 or more, a plurality of R.sup.a1's
to R.sup.a4's may each be bonded to each other to form a ring.
[0324] The metal complex dye represented by Formula (I) can be
synthesized by, for example, the method described in
JP2013-084594A, the method described in JP4298799B, the method
described in each specification of US2013/0018189A1,
US2012/0073660A1, US2012/0111410A1, and US2010/0258175A1, the
method described in Angew. Chem. Int. Ed., 2011, 50, pp. 2054-2058,
the methods described in the reference documents listed in these
documents, the patent documents regarding solar cells, known
methods, or the methods equivalent thereto.
[0325] The metal complex dye represented by Formula (I) has a
maximum absorption wavelength in a solution, preferably in a range
from 300 to 1,000 nm, more preferably in a range from 350 to 950
nm, and particularly preferably in a range from 370 to 900 nm.
[0326] Specific examples of the metal complex dye represented by
Formula (I) are shown in the following description and in Examples.
Further, the specific examples in the following description and the
specific examples in Examples also include metal complex dyes in
which at least one of --COOH's is formed into a salt of the
carboxyl group. In these metal complex dyes, examples of the
counter cation that forms a salt of a carboxyl group include the
positive ions described for the CI. The present invention is not
limited to these metal complex dyes. In a case where these metal
complex dyes have optical isomers or geometric isomers, the metal
complex dye may be any of these isomers or a mixture of these
isomers.
[0327] The specific examples in the following description and the
specific examples shown in Examples each independently represent
the specific examples of each of the ligands LA, LD, and LX,
irrespective of the specific combinations of the ligands LA, LD,
and LX in the respective specific examples. Further, in the
specific examples, Me represents methyl and TBA represents
tetrabutylammonium.
##STR00348## ##STR00349## ##STR00350## ##STR00351## ##STR00352##
##STR00353## ##STR00354## ##STR00355## ##STR00356## ##STR00357##
##STR00358## ##STR00359## ##STR00360## ##STR00361## ##STR00362##
##STR00363## ##STR00364## ##STR00365## ##STR00366## ##STR00367##
##STR00368## ##STR00369##
[0328] <Substituent Group T>
[0329] In the present invention, preferred examples of the
substituent include the groups selected from the following
substituent group T The substituent group T is a substituent group
not including the acidic group.
[0330] Incidentally, in the present specification, in a case where
there is only a simple description of a substituent, reference is
made to this substituent group T, and further, in a case where each
of the groups, for example, an alkyl group is merely described,
preferred ranges and specific examples for the corresponding group
for the substituent group T are applied.
[0331] Moreover, in the present specification, in a case where an
alkyl group is described as separate from a cycloalkyl group (for
example, the description of the substituents which may be adopted
as R.sup.AA), the alkyl group is used to mean inclusion of both of
a linear alkyl group and a branched alkyl group. On the other hand,
in a case where an alkyl group is not described as separate from a
cycloalkyl group (a case where an alkyl group is simply described),
and unless otherwise specified, the alkyl group is used to mean
inclusion of a linear alkyl group, a branched alkyl group, and a
cycloalkyl group. This shall apply to a group (an alkoxy group, an
alkylthio group, an alkenyloxy group, and the like) including a
group (an alkyl group, an alkenyl group, an alkynyl group, and the
like) which can adopt a cyclic structure, and a compound (the alkyl
esterified product and the like) including a group which can adopt
a cyclic structure. In the following description of the substituent
group T, for example, a group with a linear or branched structure
and a group with a cyclic structure may be sometimes separately
described for clarification of both groups, as in the alkyl group
and the cycloalkyl group.
[0332] Examples of the groups included in the substituent group T
include the following groups or the groups formed by the
combination of a plurality of the following groups: an alkyl group
(preferably an alkyl group having 1 to 20 carbon atoms, for
example, methyl, ethyl, isopropyl, n-butyl, t-butyl, pentyl, hexyl,
heptyl, octyl, 1-ethylpentyl, benzyl, 2-ethoxyethyl,
1-carboxymethyl, and trifluoromethyl), an alkenyl group (preferably
an alkenyl group having 2 to 20 carbon atoms, for example, vinyl,
allyl, and oleyl), an alkynyl group (preferably an alkynyl group
having 2 to 20 carbon atoms, for example, ethynyl, butynyl, and
phenylethynyl), a cycloalkyl group (preferably a cycloalkyl group
having 3 to 20 carbon atoms, for example, cyclopropyl, cyclopentyl,
cyclohexyl, and 4-methylcyclohexyl), an cycloalkenyl group
(preferably a cycloalkenyl group having 5 to 20 carbon atoms, for
example, cyclopentenyl and cyclohexenyl), an aryl group (preferably
an aryl group having 6 to 26 carbon atoms, for example, phenyl,
1-naphthyl, 4-methoxyphenyl, 2-chlorophenyl, 3-methylphenyl,
difluorophenyl, and tetrafluorophenyl), a hetero ring group
(preferably a hetero ring group having 2 to 20 carbon atoms, and
more preferably a 5- or 6-membered hetero ring group having at
least one oxygen atom, sulfur atom, or nitrogen atom. The hetero
ring encompasses an aromatic ring and an aliphatic ring. Examples
of the aromatic hetero ring group (for example, a heteroaryl group)
include the following groups: for example, 2-pyridyl, 4-pyridyl,
2-imidazolyl, 2-benzimidazolyl, 2-thiazolyl, and 2-oxazolyl), an
alkoxy group (preferably an alkoxy group having 1 to 20 carbon
atoms, for example, methoxy, ethoxy, isopropyloxy, and benzyloxy),
an alkenyloxy group (preferably an alkenyloxy group having 2 to 20
carbon atoms, for example, vinyloxy and allyloxy), an alkynyloxy
group (preferably an alkynyloxy group having 2 to 20 carbon atoms,
for example, 2-propynyloxy and 4-butynyloxy), a cycloalkyloxy group
(preferably a cycloalkyloxy group having 3 to 20 carbon atoms, for
example, cyclopropyloxy, cyclopentyloxy, cyclohexyloxy, and
4-methylcyclohexyloxy), an aryloxy group (preferably an aryloxy
group having 6 to 26 carbon atoms, for example, phenoxy,
1-naphthyloxy, 3-methylphenoxy, and 4-methoxyphenoxy), a
heterocyclic oxy group (for example, imidazolyloxy,
benzimidazolyloxy, thiazolyloxy, benzothiazolyloxy, triazinyloxy,
and purinyloxy),
[0333] an alkoxycarbonyl group (preferably an alkoxycarbonyl group
having 2 to 20 carbon atoms, for example, ethoxycarbonyl and
2-ethylhexyloxycarbonyl), a cycloalkoxycarbonyl group (preferably a
cycloalkoxycarbonyl group having 4 to 20 carbon atoms, for example,
cyclopropyloxycarbonyl, cyclopentyloxycarbonyl, and
cyclohexyloxycarbonyl), an aryloxycarbonyl group (preferably an
aryloxycarbonyl group having 6 to 20 carbon atoms, for example,
phenyloxycarbonyl, and naphthyloxycarbonyl), an amino group
(preferably an amino group having 0 to 20 carbon atoms, including
an alkylamino group, an alkenylamino group, an alkynylamino group,
a cycloalkylamino group, a cycloalkenylamino group, an arylamino
group, and a heterocyclic amino group, for example, amino,
N,N-dimethylamino, N,N-diethylamino, N-ethylamino, N-allylamino,
N-(2-propynyl)amino, N-cyclohexylamino, N-cyclohexenylamino,
anilino, pyridylamino, imidazolylamino, benzimidazolylamino,
thiazolylamino, benzothiazolylamino, and triazinylamino), a
sulfamoyl group (preferably a sulfamoyl group having 0 to 20 carbon
atoms, preferably an alkyl-, cycloalkyl-, and aryl-sulfamoyl group,
for example, N,N-dimethylsulfamoyl, N-cyclohexylsulfamoyl, and
N-phenylsulfamoyl), an acyl group (preferably an acyl group having
1 to 20 carbon atoms, for example, acetyl, cyclohexylcarbonyl, and
benzoyl), an acyloxy group (preferably an acyloxy group having 1 to
20 carbon atoms, for example, acetyloxy, cyclohexylcarbonyloxy, and
benzoyloxy), a carbamoyl group (preferably a carbamoyl group having
1 to 20 carbon atoms, preferably alkyl-, cycloalkyl-, and
aryl-carbamoyl groups, for example, N,N-dimethylcarbamoyl,
N-cyclohexylcarbamoyl, and N-phenylcarbamoyl),
[0334] an acylamino group (preferably an acylamino group having 1
to 20 carbon atoms, for example, acetylamino,
cyclohexylcarbonylamino, and benzoylamino), a sulfonamido group
(preferably a sulfonamido group having 0 to 20 carbon atoms,
preferably alkyl-, cycloalkyl-, and aryl-sulfonamido groups, for
example, methane sulfonamide, benzene sulfonamide, N-methyl methane
sulfonamide, N-cyclohexyl sulfonamide, and N-ethyl benzene
sulfonamide), an alkylthio group (preferably an alkylthio group
having 1 to 20 carbon atoms, for example, methylthio, ethylthio,
isopropylthio, pentylthio, and benzylthio), a cycloalkylthio group
(preferably a cycloalkylthio group having 3 to 20 carbon atoms, for
example, cyclopropylthio, cyclopentylthio, cyclohexylthio, and
4-methylcyclohexylthio), an arylthio group (preferably an arylthio
group having 6 to 26 carbon atoms, for example, phenylthio,
1-naphthylthio, 3-methylphenylthio, and 4-methoxyphenylthio), an
alkyl-, cycloalkyl-, and aryl-sulfonyl group (preferably a sulfonyl
group having 1 to 20 carbon atoms, for example, methylsulfonyl,
ethylsulfonyl, cyclohexylsulfonyl, and benzenesulfonyl),
[0335] a silyl group (preferably a silyl group having 1 to 20
carbon atoms, preferably alkyl-, aryl-, alkoxy-, and
aryloxy-substituted silyl groups, for example, trimethylsilyl,
triethylsilyl, triisopropylsilyl, triphenylsilyl,
diethylbenzylsilyl, and dimethylphenylsilyl), a silyloxy group
(preferably a silyloxy group having 1 to 20 carbon atoms,
preferably alkyl-, aryl-, alkoxy-, and aryloxy-substituted silyloxy
groups, for example, triethylsilyloxy, triphenylsilyloxy,
diethylbenzylsilyloxy, and dimethylphenylsilyloxy), a hydroxyl
group, a cyano group, a nitro group, and a halogen atom (for
example, a fluorine atom, a chlorine atom, a bromine atom, and
iodine atom).
[0336] Examples of the group selected from the substituent group T
more preferably include an alkyl group, an alkenyl group, a
cycloalkyl group, an aryl group, a hetero ring group, an alkoxy
group, a cycloalkoxy group, an aryloxy group, an alkoxycarbonyl
group, a cycloalkoxycarbonyl group, an amino group, an acylamino
group, a cyano group, and a halogen atom, and particularly
preferably include an alkyl group, an alkenyl group, a hetero ring
group, an alkoxy group, an alkoxycarbonyl group, an amino group, an
acylamino group, and a cyano group.
[0337] When the compound, the substituent, or the like includes an
alkyl group, an alkenyl group, or the like, these may be
substituted or unsubstituted. Further, when the compound, the
substituent, or the like includes an aryl group, a hetero ring
group, or the like, these may be a monocycle or a fused ring, and
may be substituted or unsubstituted.
[0338] Next, preferred aspects of the main members of the
photoelectric conversion element and the dye-sensitized solar cell
will be described with respect to FIGS. 1 and 2.
[0339] <Electrically Conductive Support>
[0340] The electrically conductive support is not particularly
limited as long as it has electrical conductivity and is capable of
supporting a photoconductor layer 2 or the like. The electrically
conductive support is preferably an electrically conductive support
1 formed of a material having conductivity, such as a metal, or an
electrically conductive support 41 having a glass or plastic
substrate 44 and a transparent electrically-conductive film 43
formed on the surface of the substrate 44.
[0341] Between them, the electrically conductive support 41 in
which the transparent electrically-conductive film 43 is formed by
applying an electrically conductive metal oxide onto the surface of
the substrate 44 is more preferable. Examples of the substrate 44
formed of plastics include the transparent polymer films described
in paragraph No. 0153 of JP2001-291534A. Further, as a material
which forms the substrate 44, ceramics (JP2005-135902A) or
electrically conductive resins (JP2001-160425A) can be used, in
addition to glass and plastics. As the metal oxide, tin oxide (TO)
is preferable, and indium-tin oxide (tin-doped indium oxide; ITO),
and fluorine-doped tin oxide such as tin oxide which has been doped
with tin (FTO) are particularly preferable. In this case, the
coating amount of the metal oxide is preferably 0.1 to 100 g, per
square meter of the surface area of the substrate 44. In the case
of using the electrically conductive support 41, it is preferable
that light is incident from the substrate 44.
[0342] It is preferable that the electrically conductive supports 1
and 41 are substantially transparent. The expression,
"substantially transparent", means that the transmittance of light
(at a wavelength of 300 to 1,200 nm) is 10% or more, preferably 50%
or more, and particularly preferably 80% or more.
[0343] The thickness of the electrically conductive supports 1 and
41 is not particularly limited, but is preferably 0.05 .mu.m to 10
mm, more preferably 0.1 .mu.m to 5 mm, and particularly preferably
0.3 .mu.m to 4 mm.
[0344] In the case of providing a transparent
electrically-conductive film 43, the thickness of the transparent
electrically-conductive film 43 is preferably 0.01 to 30 .mu.m,
more preferably 0.03 to 25 .mu.m, and particularly preferably 0.05
to 20 .mu.m.
[0345] The electrically conductive supports 1 and 41 may be
provided with a light management function at the surface, and may
have, for example, the anti-reflection film having a high
refractive index film and a low refractive index oxide film
alternately laminated described in JP2003-123859A, and the light
guide function described in JP2002-260746A on the surface.
[0346] <Photoconductor Layer>
[0347] As long as the photoconductor layer has semiconductor fine
particles 22 carrying the dye 21 and an electrolyte, it is not
particularly limited in terms of other configurations. Preferred
examples thereof include the photoconductor layer 2 and the
photoconductor layer 42.
[0348] --Semiconductor Fine Particles (Layer Formed by
Semiconductor Fine Particles)--
[0349] The semiconductor fine particles 22 are preferably fine
particles of chalcogenides of metals (for example, oxides,
sulfides, and selenides) or of compounds having perovskite type
crystal structures. Preferred examples of the chalcogenides of
metals include oxides of titanium, tin, zinc, tungsten, zirconium,
hafnium, strontium, indium, cerium, yttrium, lanthanum, vanadium,
niobium, or tantalum, cadmium sulfide, and cadmium selenide.
Preferred examples of the compounds having perovskite type crystal
structures include strontium titanate and calcium titanate. Among
these, titanium oxide (titania), zinc oxide, tin oxide, and
tungsten oxide are particularly preferable.
[0350] Examples of the crystal structure of titania include
structures of an anatase type, a brookite type, and a rutile type,
with the structures of an anatase type and a brookite type being
preferable. A titania nanotube, nanowire, or nanorod may be used
singly or in mixture with titania fine particles.
[0351] The particle diameter of the semiconductor fine particles 22
is expressed in terms of an average particle size using a diameter
when a projected area is converted into a circle, and is preferably
0.001 to 1 .mu.m as primary particles, and 0.01 to 100 .mu.m as an
average particle size of dispersions. Examples of the method for
coating the semiconductor fine particles 22 on the electrically
conductive supports 1 or 41 include a wet method, a dry method, and
other methods.
[0352] It is preferable that the semiconductor fine particles 22
have a large surface area so that they may adsorb a large amount of
the dye 21. For example, in a state where the semiconductor fine
particles 22 are coated on the electrically conductive support 1 or
41, the surface area is preferably 10 times or more, and more
preferably 100 times or more, with respect to the projected surface
area. The upper limit of this value is not particularly limited,
and the upper limit is usually about 5,000 times. In general, as
the thickness of the semiconductor layer 45 (having the same
definition as the photoconductor layer 2 in the photoelectric
conversion element 10) formed by the semiconductor fine particles
22 increases, the amount of dye 21 that can be carried per unit
area increases, and therefore, the light absorption efficiency
increases. However, since the diffusion distance of generated
electrons increases correspondingly, the loss due to charge
recombination also increases.
[0353] As described above, it can be expected that in the
photoelectric conversion element and the dye-sensitized solar cell,
as the diffusion distance of excited electrons is smaller, the
electron transport efficiency more increases. However, when the
thickness of the semiconductor layer is decreased, the
photoelectric conversion efficiency may be reduced in some cases.
The photoelectric conversion element and the dye-sensitized solar
cell of the present invention have the metal complex dye of the
present invention, which uses a combination of the ligand LA and
the ligand LD. Thus, even in a case where the semiconductor layer
has the same thickness as that the related art or has a smaller
thickness than that in the related art, excellent photoelectric
conversion efficiency is exerted. Thus, according to the present
invention, the effect of the film thickness of the semiconductor
layer is little and excellent photoelectric conversion efficiency
is exerted.
[0354] Although a preferred thickness of the semiconductor layer 45
(the photoconductor layer 2 in the photoelectric conversion element
10) may vary depending on the utility of the photoelectric
conversion element, the thickness is typically 0.1 to 100 .mu.m. In
the case of using the photoelectric conversion element as a
dye-sensitized solar cell, the thickness of the photoconductor
layer is more preferably 1 to 50 .mu.m, and still more preferably 3
to 30 .mu.m.
[0355] In the present invention, by using the metal complex dye
represented by Formula (I), the thickness of the semiconductor
layer 45 can be reduced. For example, among the preferred ranges,
the thickness can be adjusted to 8 .mu.m or less, and to 6 .mu.m or
less.
[0356] It is preferable that the semiconductor fine particles 22
may be calcined at a temperature of 100.degree. C. to 800.degree.
C. for 10 minutes to 10 hours after being applied on the
electrically conductive support 1 or 41, so as to bring about
cohesion of the particles. In the case of using glass as a material
for the electrically conductive support 1 or the substrate 44 is
used, the temperature is preferably 60.degree. C. to 600.degree.
C.
[0357] The coating amount of the semiconductor fine particles 22
per square meter of the surface area of the electrically conductive
support 1 or 41 is preferably 0.5 to 500 g, and more preferably 5
to 100 g.
[0358] It is preferable that a short circuit-preventing layer is
formed between the electrically conductive support 1 or 41 and the
photoconductor layer 2 or 42 so as to prevent reverse current due
to a direct contact between the electrolyte included in the
photoconductor layer 2 or 42 and the electrically conductive
support 1 or 41.
[0359] In addition, it is preferable to use a spacer S (see FIG. 2)
or a separator, so as to prevent contact between the
light-receiving electrode 5 or 40 and the counter electrode 4 or
48.
[0360] --Dye--
[0361] In the photoelectric conversion element 10 and the
dye-sensitized solar cell 20, at least one kind of metal complex
dye represented by Formula (I) is used as a sensitizing dye. The
metal complex dye represented by Formula (I) is as described
above.
[0362] In the present invention, examples of the dye that can be
used in combination with the metal complex dye of Formula (I)
include an Ru complex dye, a squarylium cyanine dye, an organic
dye, a porphyrin dye, and a phthalocyanine dye.
[0363] Examples of the Ru complex dye include the Ru complex dyes
described in JP1995-500630A (JP-H07-500630A) (in particular, the
dyes synthesized in Examples 1 to 19 described in from line 5 on
left lower column on page 5 to line 7 on right upper column on page
7), the Ru complex dyes described in JP2002-512729A (in particular,
dyes synthesized in Examples 1 to 16 described in line 3 from the
bottom of page 20 to line 23 on page 29), the Ru complex dyes
described in JP2001-59062A (in particular, the dyes described in
paragraph Nos. 0087 to 0104), the Ru complex dyes described in
JP2001-6760A (in particular, the dyes described in paragraph Nos.
0093 to 0102), the Ru complex dyes described in JP2001-253894A (in
particular, the dyes described in paragraph Nos. 0009 and 0010),
the Ru complex dyes described in JP2003-212851A (in particular, the
dyes described in paragraph No. 0005), the Ru complex dyes
described in WO2007/91525A (in particular, the dyes described in
[0067]), the Ru complex dyes described in JP2001-291534A (in
particular, the dyes described in paragraph Nos. 0120 to 0144), the
Ru complex dyes described in JP2012-012570A (in particular, the
dyes described in paragraph Nos. 0095 to 0103), the Ru complex dyes
described in JP2013-084594A (in particular, the dyes described in
paragraph Nos. 0072 to 0081 and the like), the Ru complex dyes
described in WO2013/088898A (in particular, the dyes described in
[0286] to [0293]), and the Ru complex dyes described in
WO2013/47615A (in particular, the dyes described in [0078] to
[0082]).
[0364] Examples of the squarylium cyanine dye include the
squarylium cyanine dyes described in JP1999-214730A
(JP-H11-214730A) (in particular, the dyes described in paragraph
Nos. 0036 to 0047), the squarylium cyanine dyes described in
JP2012-144688A (in particular, the dyes described in paragraph Nos.
0039 to 0046 and 0054 to 0060), and the squarylium cyanine dyes
described in JP2012-84503A (in particular, the dyes described in
paragraph Nos. 0066 to 0076 and the like).
[0365] Examples of the organic dye include the organic dyes
described in JP2004-063274A (in particular, the dyes described in
paragraph Nos. 0017 to 0021), the organic dyes described in
JP2005-123033A (in particular, the dyes described in paragraph Nos.
0021 to 0028), the organic dyes described in JP2007-287694A (in
particular, the dyes described in paragraph Nos. 0091 to 0096), the
organic dyes described in JP2008-71648A (in particular, the dyes
described in paragraph Nos. 0030 to 0034), and the organic dyes
described in WO2007/119525A (in particular, the dyes described in
paragraph No. [0024]).
[0366] Examples of the porphyrin dye include the porphyrin dyes
described in Angew. Chem. Int. Ed., 49, pp. 1 to 5 (2010), or the
like, and examples of the phthalocyanine dye include the
phthalocyanine dyes described in Angew. Chem. Int. Ed., 46, p. 8358
(2007), or the like.
[0367] As the dye to be used in combination, Ru complex dyes,
squarylium cyanine dyes, or organic dyes are preferable.
[0368] The overall amount of the dye to be used is preferably 0.01
to 100 millimoles, more preferably 0.1 to 50 millimoles, and
particularly preferably 0.1 to 10 millimoles, per square meter of
the surface area of the electrically conductive support 1 or 41.
Further, the amount of the dye 21 to be adsorbed onto the
semiconductor fine particles 22 is preferably 0.001 to 1 millimole,
and more preferably 0.1 to 0.5 millimoles, with respect to 1 g of
the semiconductor fine particles 22. By setting the amount of the
dye to such a range, the sensitization effect on the semiconductor
fine particles 22 is sufficiently obtained.
[0369] In a case where the metal complex dye represented by Formula
(I) is used in combination with another dye, the ratio of the mass
of the metal complex dye represented by Formula (I)/the mass of
another dye is preferably 95/5 to 10/90, more preferably 95/5 to
50/50, still more preferably 95/5 to 60/40, particularly preferably
95/5 to 65/35, and most preferably 95/5 to 70/30.
[0370] After the dye is carried on the semiconductor fine particles
22, the surface of the semiconductor fine particles 22 may be
treated using an amine compound. Preferred examples of the amine
compound include pyridine compounds (for example, 4-t-butylpyridine
and polyvinylpyridine). These may be used as they are in a case
where they are liquids, or may be used in a state where they are
dissolved in an organic solvent.
[0371] --Co-Adsorbent--
[0372] In the present invention, it is preferable to use a
co-adsorbent together with the metal complex dye represented by
Formula (I) or with another dye to be used in combination, if
necessary. Such a co-adsorbent which includes a co-adsorbent having
at least one acidic group (preferably a carboxyl group or a salt
thereof) is preferable, and examples thereof include a fatty acid
and a compound having a steroid skeleton.
[0373] The fatty acid may be a saturated fatty acid or an
unsaturated fatty acid, and examples thereof include a butanoic
acid, a hexanoic acid, an octanoic acid, a decanoic acid, a
hexadecanoic acid, a dodecanoic acid, a palmitic acid, a stearic
acid, an oleic acid, a linoleic acid, and a linolenic acid.
[0374] Examples of the compound having a steroid skeleton include
cholic acid, glycocholic acid, chenodeoxycholic acid, hyocholic
acid, deoxycholic acid, lithocholic acid, and ursodeoxycholic acid,
among which cholic acid, deoxycholic acid, and chenodeoxycholic
acid are preferable; and chenodeoxycholic acid are more
preferable.
[0375] A preferred co-adsorbent is a compound represented by the
following Formula (CA).
##STR00370##
[0376] In the formula, R.sup.A1 represents a substituent having an
acidic group. R.sup.A2 represents a substituent. nA represents an
integer of 0 or more.
[0377] The acidic group has the same definitions as the acidic
group in Formula (LA-1), and a preferred range thereof is also the
same.
[0378] Among these, R.sup.A1 is preferably an alkyl group
substituted with a carboxyl group, a sulfo group, or a salt
thereof, and more preferably
--CH(CH.sub.3)CH.sub.2CH.sub.2CO.sub.2H or
--CH(CH.sub.3)CH.sub.2CH.sub.2CONHCH.sub.2CH.sub.2SO.sub.3H.
[0379] Examples of R.sup.A2 include groups selected from the
substituent group T. Among those, an alkyl group, a hydroxyl group,
an acyloxy group, an alkylaminocarbonyloxy group, or an
arylaminocarbonyloxy group is preferable; and an alkyl group, a
hydroxyl group, or an acyloxy group is more preferable.
[0380] nA is preferably 2 to 4.
[0381] By making the co-adsorbent adsorbed onto the semiconductor
fine particles 22, the co-adsorbent exhibits an effect of
suppressing the inefficient association of the metal complex dye
and an effect of preventing reverse electron transfer from the
surface of the semiconductor fine particles to the redox system in
the electrolyte. The amount of the co-adsorbent to be used is not
particularly limited, and from the viewpoint of exhibiting the
above effects effectively, the amount is preferably 1 to 200 moles,
more preferably 10 to 150 moles, and particularly preferably 20 to
50 moles, with respect to 1 mole of the metal complex dye.
[0382] --Light-Scattering Layer--
[0383] In the present invention, the light-scattering layer is
different from the semiconductor layer in that the light-scattering
layer has a function of scattering incident light.
[0384] In the dye-sensitized solar cell 20, the light-scattering
layer 46 preferably contains rod-shaped or plate-shaped metal oxide
particles. Examples of the metal oxide particles to be used in the
light-scattering layer 46 include particles of the chalcogenides
(oxides) of the metals. In the case of providing the
light-scattering layer 46, it is preferable that the thickness of
the light-scattering layer is set to 10% to 50% of the thickness of
the photoconductor layer 42.
[0385] The light-scattering layer 46 is preferably the
light-scattering layer described in JP2002-289274A, and the
description of JP2002-289274A is preferably herein incorporated by
reference.
[0386] <Charge Transfer Layer>
[0387] The charge transfer layers 3 and 47 used in the
photoelectric conversion element of the present invention are
layers having a function of complementing electrons for the
oxidized forms of the dye 21, and are provided between the
light-receiving electrode 5 or 40 and the counter electrode 4 or
48.
[0388] The charge transfer layers 3 and 47 include electrolytes.
Here, the expression, "the charge transfer layer includes an
electrolyte", is used to mean inclusion of both of an aspect in
which the charge transfer layer consists of only electrolytes and
an aspect in which the charge transfer layer consists of
electrolytes and materials other than the electrolytes.
[0389] The charge transfer layers 3 and 47 may be any of a solid
form, a liquid form, a gel form, or a mixture thereof.
[0390] --Electrolyte--
[0391] Examples of the electrolyte include a liquid electrolyte
having a redox pair dissolved in an organic solvent, and a
so-called gel electrolyte in which a molten salt containing a redox
pair and a liquid having a redox pair dissolved in an organic
solvent are impregnated in a polymer matrix. Among those, from the
viewpoint of photoelectric conversion efficiency, a liquid
electrolyte is preferable.
[0392] Examples of the redox pair include a combination of iodine
and an iodide (preferably an iodide salt or an iodide ionic liquid,
and preferably lithium iodide, tetrabutylammonium iodide,
tetrapropylammonium iodide, and methylpropylimidazolium iodide), a
combination of an alkylviologen (for example, methylviologen
chloride, hexylviologen bromide, and benzylviologen
tetrafluoroborate) and a reductant thereof, a combination of a
polyhydroxybenzene (for example, hydroquinone and
naphthohydroquinone) and an oxidized form thereof, a combination of
a divalent iron complex and a trivalent iron complex (for example,
a combination of potassium ferricyanide and potassium
ferrocyanide), and a combination of a divalent cobalt complex and a
trivalent cobalt complex. Among these, a combination of iodine and
an iodide, or a combination of a divalent cobalt complex and a
trivalent cobalt complex is preferable, and a combination of iodine
and an iodide is particularly preferable.
[0393] As the cobalt complex, the complex represented by Formula
(CC) described in paragraph Nos. 0144 to 0156 of JP2014-82189A is
preferable, and the description of paragraph Nos. 0144 to 0156 of
JP2014-82189A is preferably incorporated in the present
specification.
[0394] In a case where a combination of iodine and iodide is used
as an electrolyte, it is preferable that a nitrogen-containing
aromatic cation iodide salt as a 5- or 6-membered ring is
additionally used.
[0395] The organic solvent which is used in a liquid electrolyte
and a gel electrolyte is not particularly limited, but is
preferably an aprotic polar solvent (for example, acetonitrile,
propylene carbonate, ethylene carbonate, dimethylformamide,
dimethylsulfoxide, sulfolane, 1,3-dimethylimidazolinone, and
3-methyloxazolidinone).
[0396] In particular, as the organic solvent which is used for a
liquid electrolyte, a nitrile compound, an ether compound, an ester
compound, or the like is preferable, a nitrile compound is more
preferable, and acetonitrile or methoxypropionitrile is
particularly preferable.
[0397] As a molten salt, an ionic liquid including an imidazolium
or triazolium type cation, an ionic liquid including an oxazolium
type cation, an ionic liquid including a pyridinium type cation, an
ionic liquid including a guanidium type cation, and combinations of
these are preferable. Further, these cations may be used in
combination with specific anions. Additives may be added to these
molten salts. The molten salt may have a substituent having liquid
crystalline properties. In addition, a molten salt of the quatemary
ammonium salt may also be used as the molten salt.
[0398] Other examples of the molten salts include a molten salt to
which fluidity at room temperature has been provided by mixing
lithium iodide and at least one kind of other lithium salt (for
example, lithium acetate and lithium perchlorate) with polyethylene
oxide. In this case, the amount of the polymer to be added is 1% to
50% by mass. Further, an electrolytic solution may contain
.gamma.-butyrolactone, and this .gamma.-butyrolactone increases the
diffusion efficiency of iodide ions, whereby the photoelectric
conversion efficiency is enhanced.
[0399] Examples of the polymer (polymer matrix) to be used in a
matrix of the gel electrolyte include polyacrylonitrile and
polyvinylidene fluoride.
[0400] The electrolyte may be quasi-solidified by adding a gelling
agent to an electrolytic solution formed of an electrolyte and a
solvent, followed by gelling (the quasi-solidified electrolyte may
also be hereinafter referred to as a "quasi-solidified
electrolyte"). Examples of the gelling agent include an organic
compound having a molecular weight of 1,000 or less, an
Si-containing compound having a molecular weight in the range of
500 to 5,000, an organic salt generated from a specific acidic
compound and a specific basic compound, a sorbitol derivative, and
polyvinylpyridine.
[0401] Furthermore, a method of confining a polymer matrix, a
crosslinkable polymer compound or monomer, a crosslinking agent, an
electrolyte, and a solvent in a polymer may also be used.
[0402] Preferred examples of the polymer matrix include a polymer
having a nitrogen-containing heterocycle in a repeating unit in the
main chain or in the side chain, and a crosslinked structure formed
by reacting the polymer with an electrophilic compound, a polymer
having a triazine structure, a polymer having a ureide structure, a
polymer containing a liquid crystalline compound, a polymer having
an ether bond, polyvinylidene fluoride, a methacrylate, an
acrylate, a thermosetting resin, crosslinked polysiloxane,
polyvinyl alcohol (PVA), a clathrate compound of polyalkylene
glycol with dextrin or the like, a system incorporated with an
oxygen-containing or sulfur-containing polymer, and a naturally
occurring polymer. An alkali-swellable polymer, a polymer having a
compound capable of forming a charge transfer complex of iodine
with a cation moiety within one polymer, or the like may be added
to the polymer matrix.
[0403] A system containing, as a polymer matrix, a crosslinked
polymer formed by reacting a bifunctional or higher-functional
isocyanate as one component with a functional group such as a
hydroxyl group, an amino group or a carboxyl group, may also be
used. Furthermore, a crosslinked polymer based on a hydrosilyl
group and a double-bonded compound, a crosslinking method involving
reacting polysulfonic acid, polycarboxylic acid, or the like with a
divalent or higher-valent metal ion compound, and the like may also
be used.
[0404] Examples of the solvent that can be preferably used in
combination with the quasi-solid electrolyte described above
include a specific phosphoric ester, a mixed solvent including
ethylene carbonate, and a solvent having a specific relative
permittivity. A liquid electrolyte solution may be retained in a
solid electrolyte membrane or in pores, and preferred examples of
the method for retaining the liquid electrolyte solution include a
method using an electrically conductive polymer membrane, a fibrous
solid, and a fabric-like solid such as a filter.
[0405] The electrolyte may contain aminopyridine compounds,
benzimidazole compounds, aminotriazole compounds, aminothiazole
compounds, imidazole compounds, aminotriazine compounds, urea
compounds, amide compounds, pyrimidine compounds, and heterocycles
not including nitrogen, in addition to pyridine compounds such as
4-t-butylpyridine, as an additive.
[0406] Moreover, a method of controlling the moisture content of
the electrolytic solution may be employed in order to enhance the
photoelectric conversion efficiency. Preferred examples of the
method of controlling the moisture content include a method of
controlling the concentration, and a method of adding a dehydrating
agent. The moisture content of the electrolytic solution is
preferably adjusted to 0% to 0.1% by mass.
[0407] Iodine can also be used as a clathrate compound of iodine
with cyclodextrin. Furthermore, a cyclic amidine may be used, or an
antioxidant, a hydrolysis inhibitor, a decomposition inhibitor, or
zinc iodide may be added.
[0408] A solid-state charge transport layer such as a p-type
semiconductor or a hole transport material, for example, CuI or
CuNCS, may be used in place of the liquid electrolyte and the
quasi-solid-state electrolyte as described above. Moreover, the
electrolytes described in Nature, vol. 486, p. 487 (2012) and the
like may also be used. For a solid-state charge transport layer, an
organic hole transport material may be used. Preferred examples of
the hole transport layer include electrically conductive polymers
such as polythiophene, polyaniline, polypyrrole, and polysilane; a
spiro compound in which two rings share a central element adopting
a tetrahedral structure, such as C and Si; aromatic amine
derivatives such as triarylamine; triphenylene derivatives;
nitrogen-containing heterocyclic derivatives; and liquid
crystalline cyano derivatives.
[0409] The redox pair serves as an electron carrier, and
accordingly, it is preferably contained at a certain concentration.
The concentration of the redox pair in total is preferably 0.01
mol/L or more, more preferably 0.1 mol/L or more, and particularly
preferably 0.3 mol/L or more. In this case, the upper limit is not
particularly limited, but is usually approximately 5 mol/L.
[0410] <Counter Electrode>
[0411] The counter electrodes 4 and 48 preferably work as a
positive electrode in a dye-sensitized solar cell. The counter
electrodes 4 and 48 usually have the same configurations as the
electrically conductive support 1 or 41, but in a configuration in
which strength is sufficiently maintained, a substrate 44 is not
necessarily required. A preferred structure of the counter
electrodes 4 and 48 is a structure having a high charge collecting
effect. At least one of the electrically conductive support 1 or 41
and the counter electrode 4 or 48 should be substantially
transparent so that light may reach the photoconductor layers 2 and
42. In the dye-sensitized solar cell of the present invention, the
electrically conductive support 1 or 41 is preferably transparent
to allow sunlight to be incident from the side of the electrically
conductive support 1 or 41. In this case, the counter electrodes 4
and 48 more preferably have light reflecting properties. As the
counter electrodes 4 and 48 of the dye-sensitized solar cell, glass
or plastic on which a metal or an electrically conductive oxide is
deposited is preferable, and glass on which platinum is deposited
is particularly preferable. In the dye-sensitized solar cell, a
lateral side of the cell is preferably sealed with a polymer, an
adhesive, or the like in order to prevent evaporation of
components.
[0412] The present invention can be applied to the photoelectric
conversion elements and the dye-sensitized solar cells described
in, for example, JP4260494B, JP2004-146425A, JP2000-340269A,
JP2002-289274A, JP2004-152613A, or JP1997-27352A (JP-H09-27352A).
In addition, the present invention can be applied to the
photoelectric conversion elements and the dye-sensitized solar
cells described in, for example, JP2000-90989A, JP2003-217688A,
JP2002-367686A, JP2003-323818A, JP2001-43907A, JP2005-85500A,
JP2004-273272A, JP2000-323190A, JP2000-228234A, JP2001-266963A,
JP2001-185244A, JP2001-525108A, JP2001-203377A, JP2000-100483A,
JP2001-210390A, JP2002-280587A, JP2001-273937A, JP2000-285977A, or
JP2001-320068A.
[0413] [Method for Producing Photoelectric Conversion Element and
Dye-Sensitized Solar Cell]
[0414] The photoelectric conversion element and the dye-sensitized
solar cell of the present invention can be produced using a dye
solution (the dye solution of the present invention) which contains
the metal complex dye of the present invention and a solvent.
[0415] Such a dye solution is formed of the metal complex dye of
the present invention dissolved in a solvent, and may also include
a co-adsorbent and other components, if necessary.
[0416] Examples of the solvent to be used include the solvents
described in JP2001-291534A, but are not particularly limited
thereto. In the present invention, an organic solvent is
preferable, and an alcohol solvent, an amide solvent, a nitrile
solvent, a hydrocarbon solvent, and a mixed solvent of two or more
kinds of these solvents are more preferable. As the mixed solvent,
a mixed solvent of an alcohol solvent and a solvent selected from
an amide solvent, a nitrile solvent, and a hydrocarbon solvent is
preferable; a mixed solvent of an alcohol solvent and an amide
solvent, a mixed solvent of an alcohol solvent and a hydrocarbon
solvent, and a mixed solvent of an alcohol solvent and a nitrile
solvent are more preferable; and a mixed solvent of an alcohol
solvent and an amide solvent, and a mixed solvent of an alcohol
solvent and a nitrile solvent are particularly preferable.
Specifically, a mixed solvent of at least one kind of methanol,
ethanol, propanol, butanol, and t-butanol, and at least one kind of
dimethylformamide and dimethylacetamide, and a mixed solvent of at
least one kind of methanol, ethanol, propanol, and t-butanol, and
acetonitrile are preferable.
[0417] The dye solution preferably contains a co-adsorbent, and as
the co-adsorbent, the aforementioned co-adsorbent is preferable.
Among those, the compound represented by Formula (CA) is
preferable.
[0418] Here, the dye solution of the present invention is
preferably one in which the concentrations of the metal complex dye
and the co-adsorbent have been adjusted so that the dye solution
can be used as it is during production of the photoelectric
conversion element or the dye-sensitized solar cell. In the present
invention, the dye solution of the present invention preferably
contains 0.001% to 0.1% by mass of the metal complex dye of the
present invention. The amount of the co-adsorbent to be used is as
described above.
[0419] For the dye solution, it is preferable to adjust the
moisture content, and thus in the present invention, the water
content is preferably adjusted to 0% to 0.1% by mass.
[0420] In the present invention, it is preferable to manufacture a
photoconductor layer by making the metal complex dye represented by
Formula (I) or a dye including the same on the surface of the
semiconductor fine particles, using the dye solution. That is, the
photoconductor layer is preferably formed by applying (including a
dip method) the dye solution onto the semiconductor fine particles
provided on the electrically conductive support, followed by drying
and curing.
[0421] By further providing a charge transfer layer, a counter
electrode, or the like for a light-receiving electrode including
the photoconductor layer as manufactured above, the photoelectric
conversion element or the dye-sensitized solar cell of the present
invention can be obtained.
[0422] The dye-sensitized solar cell is produced by connecting an
external circuit 6 with the electrically conductive support 1 and
the counter electrode 4 of the photoelectric conversion element
thus manufactured.
EXAMPLES
[0423] The present invention will be described below in more
detail, based on Examples, but the present invention is not limited
thereto.
[0424] Hereinafter, a method for synthesizing the metal complex dye
of the present invention will be described, but the starting
materials, the dye intermediates, and the synthesis routes are not
limited thereto.
[0425] In the present invention, the room temperature means
25.degree. C. Further, Me represents methyl, Et represents ethyl,
and TBA represents tetrabutylammonium.
[0426] The metal complex dye and the synthesis intermediate
synthesized in Example 1 were identified by mass spectrum (MS)
measurement and .sup.1H-NMR measurement.
[0427] The TBA salt of the synthesized metal complex dye becomes
the same mass as the metal complex dye which is electrically
neutral by protonization in the MS measurement, and therefore the
results of the MS measurement are omitted for the TBA salt.
Example 1 (Synthesis of Metal Complex Dye)
[0428] Metal complex dyes (D-1) to (D-21) synthesized in the
present Example are shown below.
##STR00371## ##STR00372## ##STR00373## ##STR00374## ##STR00375##
##STR00376## ##STR00377## ##STR00378## ##STR00379##
##STR00380##
[0429] (Synthesis of Metal Complex Dye (D-1) and Metal Complex Dye
(D-1TBA))
[0430] According to the following scheme, a metal complex dye (D-1)
and a metal complex dye (D1TBA) were synthesized.
##STR00381## ##STR00382## ##STR00383##
[0431] (i) Synthesis of Compound (1-2)
[0432] The compound (1-1) (16.9 g, 100 mmol), diphenylamine (17.9
g, 110 mmol), and t-butoxy sodium (28.8 g, 300 mmol) were added to
toluene (300 mL), and the mixture was repeatedly subjected to
pressure reduction (vacuum) and nitrogen gas substitution to
perform degassing. Palladium acetate (1.1 g, 5.0 mmol) and
tri(t-butyl) phosphine (2.0 g, 10 mmol) were added thereto, and the
obtained mixture was warmed and allowed to undergo a reaction for 2
hours under refluxing. Thereafter, the reaction mixture was left to
be cooled, a saturated aqueous ammonium chloride solution was added
thereto and the reaction product was extracted. The organic phase
was washed with saturated saline and dried over magnesium sulfate.
Magnesium sulfate was filtered off and the filtrate was
concentrated to obtain a crude product. The obtained crude product
was purified by silica gel column chromatography (eluent:
toluene/hexane=1/9) to obtain a compound (1-2) (17.5 g, a yield of
70%).
[0433] (ii) Synthesis of Compound (1-5)
[0434] A solution obtained by dissolving the compound (1-2) (2.12
g, 9.18 mmol) in tetrahydrofuran (THF, 30 mL) was cooled to
-78.degree. C., and n-butyllithium (1.6 M hexane solution, 8.1 mL)
was added dropwise thereto for 10 minutes. The compound (1-2) was
reacted with n-butyllithium at -78.degree. C. for 1 hour, and then
a compound (1-3) (2.51 g, 13.5 mmol) was added dropwise to the
reaction solution for 5 minutes. The obtained solution was
additionally stirred at -78.degree. C. for 1 hour and then warmed
to 0.degree. C., and a saturated aqueous ammonium chloride solution
was added thereto. The reaction product was extracted with ethyl
acetate, and the organic phase was washed with saturated saline,
and dried over magnesium sulfate. Magnesium sulfate was filtered
off and the filtrate was concentrated to obtain a compound
(1-4).
[0435] A total amount of the obtained compound (1-4),
2-chloro-4-iodopyridine (2.00 g, 8.35 mmol), and potassium
carbonate (2.54 g, 18.4 mmol) were added to THF/H.sub.2O (9:1, 90
mL), and the mixture was degassed by nitrogen gas bubbling.
Palladium acetate (94 mg, 0.42 mmol) and
2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (SPhos, 0.35 g,
0.84 mmol) were added thereto, and the mixture was warmed and
allowed to undergo a reaction for 5 hours under refluxing.
Thereafter, the reaction mixture was left to be cooled, and the
reaction product was extracted with water and ethyl acetate. The
organic phase was washed with saturated saline and dried over
magnesium sulfate. Magnesium sulfate was filtered off and the
filtrate was concentrated to obtain a crude product. The obtained
crude product was purified by silica gel column chromatography
(eluent: chloroform/hexane=1/1) to obtain a compound (1-5) (2.45 g,
a yield of 81%).
[0436] The compound (1-5) was identified from the following
data.
[0437] Chemical shift .sigma. (ppm) by .sup.1H-NMR (400 MHz,
solvent: CDCl.sub.3, internal standard substance: tetramethylsilane
(TMS))=6.58 (d, 1H), 7.12 (t, 2H), 7.18-7.35 (m, 11H), 8.24 (d,
1H)
[0438] MS (ESI.sup.+) m/z: 363 ([M+H].sup.+)
[0439] (iii) Synthesis of Compound (1-7)
[0440] The compound (1-5) (1.39 g, 3.77 mmol) and hexamethyl ditin
(1.43 g, 4.35 mmol) were added to toluene (75 mL), and the mixture
was repeatedly subjected to pressure reduction (vacuum) and
nitrogen gas substitution to perform degassing.
Tetrakis(triphenylphosphine)palladium (0) (1.31 g, 1.13 mmol) was
added thereto, and the mixture was warmed and allowed to undergo a
reaction for 8 hours under refluxing. A compound (1-6) (1.10 g,
2.90 mmol) was added to the obtained liquid, and the mixture was
additionally allowed to undergo a reaction for 3 hours under
refluxing. The obtained reaction mixture was left to be cooled and
then concentrated, and the concentrated residue was purified by
silica gel column chromatography (eluent: ethyl
acetate/chloroform=1/9) to obtain a compound (1-7) (0.91 g, a yield
of 50%) which is a diethyl esterified product of a terpyridine
compound.
[0441] The compound (1-7) was identified from the following
data.
[0442] Chemical shift .sigma. (ppm) by .sup.1H-NMR (400 MHz,
solvent: CDCl.sub.3, internal standard substance: tetramethylsilane
(TMS))=1.38 (t, 3H), 1.47 (t, 3H), 4.37 (q, 2H), 4.51 (q, 2H), 6.68
(d, 1H), 7.10 (t, 2H), 7.22 (d, 4H), 7.31 (t, 4H), 7.43 (d, 1H),
7.49 (d, 1H), 7.92 (d, 1H), 8.66 (d, 1H), 8.75 (s, 1H), 8.89 (d,
1H), 9.02 (s, 2H), 9.15 (s, 1H)
[0443] MS (ESI.sup.+) m/z: 627 ([M+H].sup.+)
[0444] (iv) Synthesis of Compound (1-8)
[0445] The compound (1-7) (400 mg, 0.64 mmol) and ruthenium
trichloride trihydrate (167 mg, 0.64 mmol) were added to ethanol
(40 mL), and the mixture was allowed to undergo a reaction for 2
hours under refluxing. The reaction mixture was left to be cooled,
and the precipitate was collected by filtration and washed with
ethanol to obtain a compound (1-8) (450 mg, a yield of 84%). The
obtained compound (1-8) was used in the next step without
purification.
[0446] (v) Synthesis of Compound (1-10)
[0447] The compound (1-8) (450 mg, 0.54 mmol) and a compound (1-9)
(205 mg, 0.54 mmol) were added to N,N-dimethylformamide (DMF, 18
mL), and mixture was allowed to undergo a reaction for 3 hours
under refluxing. The reaction mixture was left to be cooled and
then concentrated, and the concentrated residue was purified by
silica gel column chromatography (eluent: chloroform) to obtain a
compound (1-10) (302 mg, a yield of 44%).
[0448] The compound (1-10) was identified from the following
data.
[0449] Chemical shift .sigma. (ppm) by .sup.1H-NMR (400 MHz,
solvent: CDCl.sub.3, internal standard substance: tetramethylsilane
(TMS))=0.90 (t, 3H), 1.3-1.6 (m, 12H), 1.77 (m, 2H), 2.92 (t, 2H),
4.45 (q, 2H), 4.59 (q, 2H), 6.55 (d, 1H), 6.75 (s, 1H), 7.1-7.4 (m,
13H), 7.45 (d, 1H), 7.56 (d, 1H), 7.64 (d, 1H), 7.71 (d, 1H), 7.87
(s, 1H), 8.02 (d, 1H), 8.14 (s, 1H), 8.69 (s, 2H), 8.79 (s, 1H),
10.03 (d, 1H)
[0450] MS (ESI.sup.+) m/z: 1142 ([M+H].sup.+)
[0451] (vi) Synthesis of Compound (1-11)
[0452] The compound (1-10) (300 mg, 0.26 mmol) and ammonium
thiocyanate (200 mg, 2.63 mmol) were added to a mixture of DMF (30
mL) and water (3 mL), and the mixture was allowed to undergo a
reaction at 100.degree. C. for 2 hours. The reaction mixture was
left to be cooled and then concentrated, and the concentrated
residue was purified by silica gel column chromatography (eluent:
ethyl acetate/chloroform=1/9) to obtain a compound (1-11) (128 mg,
a yield of 37%).
[0453] The compound (1-11) was identified from the following
data.
[0454] Chemical shift .sigma. (ppm) by .sup.1H-NMR (400 MHz,
solvent: CDCl.sub.3, internal standard substance: tetramethylsilane
(TMS))=0.91 (t, 3H), 1.3-1.6 (m, 12H), 1.79 (m, 2H), 2.92 (t, 2H),
4.47 (q, 2H), 4.63 (q, 2H), 6.57 (d, 1H), 6.73 (s, 1H), 7.1-7.4 (m,
13H), 7.47 (d, 1H), 7.55 (d, 1H), 7.60 (d, 1H), 7.74 (d, 1H), 7.85
(s, 1H), 7.95 (d, 1H), 8.10 (s, 1H), 8.68 (s, 2H), 8.78 (s, 1H),
9.51 (d, 1H)
[0455] MS (ESI.sup.+) m/z: 1165 ([M+H].sup.+)
[0456] (vii) Synthesis of Metal Complex Dye (D-1)
[0457] The compound (1-11) (120 mg, 0.10 mmol) was added to DMF (24
mL), and a 3 M aqueous sodium hydroxide solution (1.2 mL) was added
dropwise thereto. The mixture was allowed to undergo a reaction at
room temperature for 30 minutes, and then the mixture was adjusted
to have acidity (pH=2.5) by the addition of a 1 M
trifluoromethanesulfonic acid solution in methanol. Water (50 mL)
was added to the obtained liquid, and the precipitated solid was
collected by filtration, washed with water, and then dried in vacuo
to obtain a metal complex dye (D-1) (100 mg, a yield of 88%).
[0458] The metal complex dye (D-1) was identified from the
following data.
[0459] MS (ESI.sup.+) m/z: 1109 ([M+H].sup.+)
[0460] (viii) Synthesis of Metal Complex Dye (D-1TBA)
[0461] Into an eggplant flask were introduced the metal complex dye
(D-1) (70 mg) and a 10% MeOH solution (0.160 g) of
tetrabutylammonium hydroxide (TBAOH), and the mixture was allowed
to undergo a reaction at room temperature. The obtained reaction
solution was concentrated to obtain 85 mg of a metal complex dye
(D-1TBA).
[0462] (Synthesis of Metal Complex Dye (D-2) and Metal Complex Dye
(D-2TBA))
[0463] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of 2-bromobithiophene was
used instead of the compound (1-1) in the synthesis of the metal
complex dye (D-1), a metal complex dye (D-2) was synthesized.
[0464] The metal complex dye (D-2) was identified from the
following data.
[0465] MS (ESI.sup.+) m/z: 1191 ([M+H].sup.+)
[0466] Furthermore, the following compound (2-1) which is an
intermediate (a diethyl esterified product of a terpyridine
compound) was identified from the following data.
[0467] Chemical shift .sigma. (ppm) by .sup.1H-NMR (400 MHz,
solvent: CDCl.sub.3, internal standard substance: tetramethylsilane
(TMS))=1.44 (t, 3H), 1.47 (t, 3H), 4.46 (q, 2H), 4.50 (q, 2H), 6.62
(d, 1H), 7.0-7.4 (m, 12H), 7.52 (d, 1H), 7.57 (d, 1H), 7.95 (d,
1H), 8.71 (d, 1H), 8.83 (s, 1H), 8.90 (d, 1H), 9.04 (s, 2H), 9.19
(s, 1H)
[0468] MS (ESI.sup.+) m/z: 709 ([M+H].sup.+)
##STR00384##
[0469] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-2) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-2TBA) was synthesized.
[0470] (Synthesis of Metal Complex Dye (D-3) and Metal Complex Dye
(D-3TBA))
[0471] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of
di(4-methoxyphenyl)amine was used instead of diphenylamine in the
synthesis of the metal complex dye (D-1), a metal complex dye (D-3)
was synthesized.
[0472] The metal complex dye (D-3) was identified from the
following data.
[0473] MS (ESI.sup.+) m/z: 1169 ([M+H].sup.+)
[0474] Furthermore, the following compound (3-1) and the following
compound (3-2) which are each an intermediate (a diethyl esterified
product of a terpyridine compound) were each identified from the
following data.
[0475] Compound (3-1)
[0476] Chemical shift .sigma. (ppm) by .sup.1H-NMR (400 MHz,
solvent: CDCl.sub.3, internal standard substance: tetramethylsilane
(TMS))=1.42 (t, 3H), 1.46 (t, 3H), 3.81 (s, 6H), 4.40 (q, 2H), 4.51
(q, 2H), 6.42 (d, 1H), 6.87 (d, 4H), 7.18 (d, 4H), 7.35 (d, 1H),
7.44 (d, 1H), 7.93 (d, 1H), 8.60 (d, 1H), 8.70 (s, 1H), 8.89 (d,
1H), 9.00 (s, 2H), 9.14 (s, 1H) MS (ESI.sup.+) m/z: 687
([M+H].sup.+)
[0477] Compound (3-2)
[0478] Chemical shift .sigma. (ppm) by .sup.1H-NMR (400 MHz,
solvent: CDCl.sub.3, internal standard substance: tetramethylsilane
(TMS))=0.91 (t, 3H), 1.1-1.7 (m, 14H), 1.78 (m, 2H), 2.92 (t, 2H),
3.83 (s, 6H), 4.46 (q, 2H), 4.61 (q, 2H), 6.27 (br, 1H), 6.74 (s,
1H), 6.89 (d, 4H), 7.14 (d, 2H), 7.20 (d, 4H), 7.28 (d, 1H),
7.4-7.5 (m, 2H), 7.60 (d, 1H), 7.73 (d, 1H), 7.85 (s, 1H), 7.95 (d,
1H), 8.04 (s, 1H), 8.67 (s, 2H), 8.76 (s, 1H), 9.50 (d, 1H)
[0479] MS (ESI.sup.+) m/z: 1225 ([M+H].sup.+)
##STR00385##
[0480] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-3) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-3TBA) was synthesized.
[0481] (Synthesis of Metal Complex Dye (D-4) and Metal Complex Dye
(D-4TBA))
[0482] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of di(2-fluorenyl)amine
was used instead of diphenylamine in the synthesis of the metal
complex dye (D-1), a metal complex dye (D-4) was synthesized.
[0483] The metal complex dye (D-4) was identified from the
following data.
[0484] MS (ESI.sup.+) m/z: 1341 ([M+H].sup.+)
[0485] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-4) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-4TBA) was synthesized.
[0486] (Synthesis of Metal Complex Dye (D-5) and Metal Complex Dye
(D-5TBA))
[0487] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of
2-bromo-3,4-ethylenedioxythiophene was used instead of the compound
(1-1) in the synthesis of the metal complex dye (D-1), a metal
complex dye (D-5) was synthesized.
[0488] The metal complex dye (D-5) was identified from the
following data.
[0489] MS (ESI.sup.+) m/z: 1167 ([M+H].sup.+)
[0490] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-5) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-5TBA) was synthesized.
[0491] (Synthesis of Metal Complex Dye (D-6) and Metal Complex Dye
(D-6TBA))
[0492] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of the following compound
(6-1) was used instead of the compound (1-9) in the synthesis of
the metal complex dye (D-1), a metal complex dye (D-6) was
synthesized.
[0493] The metal complex dye (D-6) was identified from the
following data.
[0494] MS (ESI.sup.+) m/z: 1187 ([M+H].sup.+)
##STR00386##
[0495] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-6) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-6TBA) was synthesized.
[0496] (Synthesis of Metal Complex Dye (D-7) and Metal Complex Dye
(D-7TBA))
[0497] In the same manner as in the synthesis of the metal complex
dye (D-1) except that, an equimolar amount of the following
compound (7-1) was used instead of the compound (1-9) in the
synthesis of the metal complex dye (D-1), a metal complex dye (D-7)
was synthesized.
[0498] The metal complex dye (D-7) was identified from the
following data.
[0499] MS (ESI.sup.+) m/z: 1069 ([M+H].sup.+)
##STR00387##
[0500] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-7) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-7TBA) was synthesized.
[0501] (Synthesis of Metal Complex Dye (D-8) and Metal Complex Dye
(D-8TBA))
[0502] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of the following compound
(8-1) instead of the compound (1-9) was reacted with the compound
(1-8), and a reaction for synthesizing the compound (1-11) from the
compound (1-10) was not carried out in the synthesis of the metal
complex dye (D-1), a metal complex dye (D-8) was synthesized.
[0503] The metal complex dye (D-8) was identified from the
following data.
[0504] MS (ESI.sup.+) m/z: 1323 ([M+H].sup.+)
##STR00388##
[0505] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-8) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-8TBA) was synthesized.
[0506] (Synthesis of Metal Complex Dye (D-9) and Metal Complex Dye
(D-9TBA))
[0507] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of the following compound
(9-1) was used instead of the compound (1-2), and an equimolar
amount of the following compound (9-2) was used instead of the
compound (1-9) in the synthesis of the metal complex dye (D-1), a
metal complex dye (D-9) was synthesized.
[0508] The metal complex dye (D-9) was identified from the
following data.
[0509] MS (ESI.sup.+) m/z: 1324 ([M+H].sup.+)
##STR00389##
[0510] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-9) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-9TBA) was synthesized.
[0511] (Synthesis of Metal Complex Dye (D-10) and Metal Complex Dye
(D-10TBA))
[0512] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of
2-dimethylaminothiophene was used instead of the compound (1-2) in
the synthesis of the metal complex dye (D-1), a metal complex dye
(D-10) was synthesized. The metal complex dye (D-10) was identified
from the following data.
[0513] MS (ESI.sup.+) m/z: 985 ([M+H].sup.+)
[0514] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-10) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-10TBA) was synthesized.
[0515] (Synthesis of Metal Complex Dye (D-11) and Metal Complex Dye
(D-11TBA))
[0516] In the same manner as in the synthesis of the metal complex
dye (D-1) except that synthesis of the compound (1-10) from the
compound (1-8) was not carried out and the compound (1-8) was
reacted with ammonium thiocyanate in the synthesis of the metal
complex dye (D-1), a metal complex dye (D-11) was synthesized. The
metal complex dye (D-11) was identified from the following
data.
[0517] MS (ESI.sup.-) m/z: 846([M].sup.-)
[0518] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-11) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-11TBA) was synthesized.
[0519] (Synthesis of Metal Complex Dye (D-12) and Metal Complex Dye
(D-12TBA))
[0520] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of the following compound
(12-1) was used instead of the compound (1-9) in the synthesis of
the metal complex dye (D-1), a metal complex dye (D-12) was
synthesized.
[0521] The metal complex dye (D-12) was identified from the
following data.
[0522] MS (ESI.sup.+) m/z: 1071 ([M+H].sup.+)
##STR00390##
[0523] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-12) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-12TBA) was synthesized.
[0524] (Synthesis of Metal Complex Dye (D-13) and Metal Complex Dye
(D-13TBA))
[0525] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of the following compound
(13-1) was used instead of the compound (1-9) in the synthesis of
the metal complex dye (D-1), a metal complex dye (D-13) was
synthesized.
[0526] The metal complex dye (D-13) was identified from the
following data.
[0527] MS (ESI.sup.+) m/z: 1139 ([M+H].sup.+)
##STR00391##
[0528] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-13) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-13TBA) was synthesized.
[0529] (Synthesis of Metal Complex Dye (D-14) and Metal Complex Dye
(D-14TBA))
[0530] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of the following compound
(14-1) was used instead of the compound (1-9) in the synthesis of
the metal complex dye (D-1), a metal complex dye (D-14) was
synthesized.
[0531] The metal complex dye (D-14) was identified from the
following data.
[0532] MS (ESI.sup.+) m/z: 1174 ([M+H].sup.+)
##STR00392##
[0533] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-14) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-14TBA) was synthesized.
[0534] (Synthesis of Metal Complex Dye (D-15) and Metal Complex Dye
(D-15TBA))
[0535] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of
bis(4-tert-butylphenyl)amine was used instead of diphenylamine in
the synthesis of the metal complex dye (D-1), a metal complex dye
(D-15) was synthesized.
[0536] The metal complex dye (D-15) was identified from the
following data.
[0537] MS (ESI.sup.+) m/z: 1221 ([M+H].sup.+)
[0538] Furthermore, the compound (15-1) which is an intermediate (a
diethyl esterified product of a terpyridine compound) was
identified from the following data.
[0539] Chemical shift .sigma. (ppm) by .sup.1H-NMR (400 MHz,
solvent: CDCl.sub.3, internal standard substance: tetramethylsilane
(TMS))=1.32 (s, 18H), 1.38 (t, 3H), 1.47 (t, 3H), 4.37 (q, 2H),
4.49 (q, 2H), 6.63 (d, 1H), 7.14 (d, 4H), 7.31 (d, 4H), 7.42 (d,
1H), 7.49 (d, 1H), 7.93 (d, 1H), 8.63 (d, 1H), 8.75 (s, 1H), 8.89
(d, 1H), 9.02 (s, 2H), 9.15 (s, 1H)
[0540] MS (ESI.sup.+) m/z: 739 ([M+H].sup.+)
##STR00393##
[0541] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-15) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-15TBA) was synthesized.
[0542] (Synthesis of Metal Complex Dye (D-16) and Metal Complex Dye
(D-16TBA))
[0543] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of
bis(4-tert-butylphenyl)amine was used instead of diphenylamine and
an equimolar amount of the following compound (16-1) was used
instead of compound (1-9) in the synthesis of the metal complex dye
(D-1), a metal complex dye (D-16) was synthesized.
[0544] The metal complex dye (D-16) was identified from the
following data.
[0545] MS (ESI.sup.+) m/z: 1334 ([M+H].sup.+)
##STR00394##
[0546] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-16) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-16TBA) was synthesized.
[0547] (Synthesis of Metal Complex Dye (D-17) and Metal Complex Dye
(D-17TBA))
[0548] In the same manner as in the synthesis of the metal complex
dye (D-1) except that an equimolar amount of
2-bromo-3-hexylthiophene was used instead of the compound (1-1),
and an equimolar amount of bis(4-tert-butylphenyl)amine was used
instead of diphenylamine in the synthesis of the metal complex dye
(D-1), a metal complex dye (D-17) was synthesized.
[0549] The metal complex dye (D-17) was identified from the
following data.
[0550] MS (ESI.sup.+) m/z: 1305 ([M+H].sup.+)
[0551] Furthermore, the following compound (17-1) and the following
compound (17-2) which are each an intermediate (a diethyl
esterified product of a terpyridine compound) were each identified
from the following data.
[0552] Compound (17-1)
[0553] Chemical shift .sigma. (ppm) by .sup.1H-NMR (400 MHz,
solvent: CDCl.sub.3, internal standard substance: tetramethylsilane
(TMS))=0.82 (t, 3H), 1.1-1.6 (m, 32H), 2.34 (t, 2H), 4.32 (q, 2H),
4.50 (m, 2H), 7.07 (d, 4H), 7.2-7.3 (m, 4H), 7.46 (s, 1H), 7.51 (d,
1H), 7.92 (d, 1H), 8.68 (d, 1H), 8.76 (s, 1H), 8.89 (d, 1H), 9.02
(s, 1H), 9.03 (s, 1H), 9.16 (s, 1H)
[0554] MS (ESI.sup.+) m/z: 823 ([M+H].sup.+)
[0555] Compound (17-2)
[0556] Chemical shift .sigma. (ppm) by .sup.1H-NMR (400 MHz,
solvent: CDCl.sub.3, internal standard substance: tetramethylsilane
(TMS))=0.82 (t, 3H), 0.90 (t, 3H), 1.1-1.7 (m, 38H), 1.78 (m, 2H),
2.28 (t, 2H), 2.93 (t, 2H), 4.47 (q, 2H), 4.63 (q, 2H), 6.74 (s,
1H), 7.02 (d, 4H), 7.14 (d, 1H), 7.2-7.4 (m, 6H), 7.36 (s, 1H),
7.47 (d, 1H), 7.55-7.65 (m, 2H), 7.75 (d, 1H), 7.86 (s, 1H), 7.96
(d, 1H), 8.19 (s, 1H), 8.69 (s, 1H), 8.72 (s, 1H), 8.80 (s, 1H),
9.52 (s, 1H)
[0557] MS (ESI.sup.+) m/z: 1361 ([M+H].sup.+)
##STR00395##
[0558] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-17) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-17TBA) was synthesized.
[0559] (Synthesis of Metal Complex Dye (D-18) and Metal Complex Dye
(D-18TBA))
[0560] In the same manner as in the synthesis of the metal complex
dye (D-1) except that the compound (17-1) was used instead of the
compound (1-7) and the following compound (18-1) was used instead
of the compound (1-9) in the synthesis of the metal complex dye
(D-1), a metal complex dye (D-18) was synthesized.
[0561] The metal complex dye (D-18) was identified from the
following data.
[0562] MS (ESI.sup.+) m/z: 1305 ([M+H].sup.+)
##STR00396##
[0563] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-18) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-18TBA) was synthesized.
[0564] (Synthesis of Metal Complex Dye (D-19) and Metal Complex Dye
(D-19TBA))
[0565] In the same manner as in the synthesis of the metal complex
dye (D-1) except that the compound (17-1) was used instead of the
compound (1-7) and the compound (16-1) was used instead of the
compound (1-9) in the synthesis of the metal complex dye (D-1), a
metal complex dye (D-19) was synthesized.
[0566] The metal complex dye (D-19) was identified from the
following data.
[0567] MS (ESI.sup.+) m/z: 1418 ([M+H].sup.+)
[0568] Furthermore, the following compound (19-1) which is an
intermediate was identified from the following data.
[0569] Chemical shift .sigma. (ppm) by .sup.1H-NMR (400 MHz,
solvent: CDCl.sub.3, internal standard substance: tetramethylsilane
(TMS))=0.84 (t, 3H), 1.1-1.6 (m, 50H), 2.29 (t, 2H), 4.48 (q, 2H),
4.61 (m, 2H), 6.42 (s, 1H), 6.89 (d, 1H), 7.02 (d, 4H), 7.15 (s,
1H), 7.2-7.4 (m, 10H), 7.50 (d, 4H), 7.69 (d, 1H), 7.78 (d, 1H),
8.06 (d, 1H), 8.17 (s, 1H), 8.66 (s, 1H), 8.68 (s, 1H), 8.75 (s,
1H), 9.01 (s, 1H)
[0570] MS (ESI.sup.+) m/z: 1475 ([M+H].sup.+)
##STR00397##
[0571] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-19) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-19TBA) was synthesized.
[0572] (Synthesis of Metal Complex Dye (D-20) and Metal Complex Dye
(D-20TBA))
[0573] In the same manner as in the synthesis of the metal complex
dye (D-1) except that the following compound (20-1) was used
instead of the compound (1-9) in the synthesis of the metal complex
dye (D-1), a metal complex dye (D-20) was synthesized.
[0574] The metal complex dye (D-20) was identified from the
following data.
[0575] MS (ESI.sup.+) m/z: 1220 ([M+H].sup.+)
##STR00398##
[0576] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-20) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-20TBA) was synthesized.
[0577] (Synthesis of Metal Complex Dye (D-21) and Metal Complex Dye
(D-21TBA))
[0578] In the same manner as in the synthesis of the metal complex
dye (D-1) except that the following compound (21-1) was used
instead of the compound (1-9) in the synthesis of the metal complex
dye (D-1), a metal complex dye (D-21) was synthesized.
[0579] The metal complex dye (D-21) was identified from the
following data.
[0580] MS (ESI.sup.+) m/z: 1064 ([M+H].sup.+)
##STR00399##
[0581] Furthermore, in the same manner as in the synthesis of the
metal complex dye (D-1TBA) except that an equimolar amount of the
metal complex dye (D-21) was used instead of the metal complex dye
(D-1) in the synthesis of the metal complex dye (D-1TBA), a metal
complex dye (D-21TBA) was synthesized.
[0582] (Measurement of Visible Absorption Spectrum)
[0583] The visible absorption spectrum of the synthesized metal
complex dye (D-1) was measured.
[0584] The metal complex dye (D-1) was dissolved in DMF to prepare
a DMF solution having a concentration of the metal complex dye
(D-1) of 17 .mu.mole/L. Further, the metal complex dye (D-1) was
dissolved in a tetrabutylammonium hydroxide (TBAOH) solution (in
methanol) having a concentration of 340 mmol/L to prepare a TBAOH
solution having a concentration of the metal complex dye (D-1) of
17 .mu.mole/L. By using this measurement solution, the light
absorption spectrum of the metal complex dye (D-1) was measured. As
the measurement device, "UV-3600" (manufactured by Shimadzu
Corporation) was used.
[0585] The visible absorption spectrum of the DMF solution is shown
in FIG. 3. The visible absorption spectrum of the
tetrabutylammonium hydroxide solution at 340 mmol/L is shown in
FIG. 4. Further, the visible absorption spectrum of the modeled
semiconductor layer in which the metal complex dye (D-1) was
adsorbed onto semiconductor fine particles (fine particles of
titanium oxide) in accordance with "(Adsorption of Dye)" in Example
2 which will be described later is shown in FIG. 5. In FIGS. 3 and
4, .epsilon. on the vertical axis is a molar light absorption
coefficient (L/molcm). In FIG. 5, Abs on the vertical axis is an
absorbance.
[0586] From FIGS. 3 to 5, it can be seen that all the visible
absorption spectra are similar to each other. Further, in
comparison between the visible absorption spectrum of the following
comparative compound c-4 described in FIG. 3 of US2012/0247561A and
the visible absorption spectra of FIGS. 3 to 5, it can be seen that
all the visible absorption spectra of the metal complex dye (D-1)
have increased light absorption coefficients in a long-wavelength
region at around a wavelength of 700 nm.
Example 2 (Production of Dye-Sensitized Solar Cell)
[0587] Using each of the metal complex dyes (D-1) to (D-21) and
(D-1TBA) to (D-21TBA) synthesized in Example 1 or the following
comparative compounds (c-1) to (c-4), a dye-sensitized solar cell
20 (in a scale of 5 mm.times.5 mm) shown in FIG. 2 was produced.
The production was carried out according to the procedure shown
below. Each of the following performance of the produced
dye-sensitized solar cell 20 was evaluated.
[0588] (Manufacture of Light-Receiving Electrode Precursor [A])
[0589] An electrically conductive support 41 was manufactured in
which a fluorine-doped SnO.sub.2 electrically-conductive film
(transparent electrically-conductive film 43, film thickness of 500
nm) was formed on a glass substrate (substrate 44, thickness of 4
mm). Further, a titania paste "18NR-T" (manufactured by DyeSol) was
screen-printed on the SnO.sub.2 electrically-conductive film,
followed by drying at 120.degree. C. Then, the dried titania paste
"18NR-T" was screen-printed again, followed by drying at
120.degree. C. for 1 hour. Thereafter, the dried titania paste was
calcined at 500.degree. C. in air to form a semiconductor layer 45
(layer thickness; 10 .mu.m). Further, a titania paste "18NR-AO"
(manufactured by DyeSol) was screen-printed on this semiconductor
layer 45, followed by drying at 120.degree. C. for 1 hour. Then,
the dried titania paste was calcined at 500.degree. C. to form a
light-scattering layer 46 (layer thickness; 5 .mu.m) on the
semiconductor layer 45.
[0590] Thus, a photoconductor layer 42 (the area of the
light-receiving surface; 5 mm.times.5 mm, layer thickness; 15
.mu.m, a metal complex dye being not carried) was formed on the
SnO.sub.2 electrically-conductive film, thereby manufacturing a
light-receiving electrode precursor [A] not carrying a metal
complex dye.
[0591] (Manufacture of Light-Receiving Electrode Precursor [B])
[0592] An electrically conductive support 41 was manufactured in
which a fluorine-doped SnO.sub.2 electrically-conductive film
(transparent electrically-conductive film 43, film thickness; 500
nm) was formed on a glass substrate (substrate 44, thickness of 4
mm). Further, a titania paste "18NR-T" (manufactured by DyeSol) was
screen-printed on this SnO.sub.2 electrically-conductive film,
followed by drying at 120.degree. C. Then, the dried titania paste
was calcined at 500.degree. C. in air to form a semiconductor layer
45 (the area of the light-receiving surface; 5 mm.times.5 mm, layer
thickness; 6 .mu.m).
[0593] Thus, a photoconductor layer 42 (the area of the
light-receiving surface; 5 mm.times.5 mm, layer thickness; 6 .mu.m,
a metal complex dye being not carried) not having the
light-scattering layer 46 provided thereon was formed on the
SnO.sub.2 electrically-conductive film, thereby manufacturing a
light-receiving electrode precursor [B] not carrying a metal
complex dye.
[0594] (Adsorption of Dye)
[0595] Next, each of the metal complex dyes ((D-1) to (D-21) and
(D-1TBA) to (D-21TBA)) that had been synthesized in Example 1 was
carried on the photoconductor layer 42 not carrying a metal complex
dye, in the following manner. First, each of the metal complex dyes
was dissolved in a mixed solvent of t-butanol and acetonitrile at
1:1 (volume ratio) to 2.times.10.sup.-4 mol/L. Further, 30 mol of
cholic acid as a co-adsorbent was added to one mol of the metal
complex dye, thereby preparing each of dye solutions. Next, the
light-receiving electrode precursor [A] was immersed in each of the
dye solutions at 25.degree. C. for 20 hours, and dried after
pulling out from the dye solution.
[0596] Thus, each of light-receiving electrodes 40 having the
respective metal complex dyes carried on the light-receiving
electrode precursor [A] was manufactured.
[0597] Each of the metal complex dyes was similarly carried on the
light-receiving electrode precursor [B] to manufacture each of
light-receiving electrodes 40 having the respective metal complex
dyes carried on the light-receiving electrode precursor [B].
[0598] (Assembly of Dye-Sensitized Solar Cell)
[0599] Then, a platinum electrode (thickness of a thin film with
Pt; 100 nm) having the same shape and size as those of the
electrically conductive support 41 was manufactured as a counter
electrode 48. Further, 0.1 M (mol/L) of iodine, 0.1 M of lithium
iodide, 0.5 M of 4-t-butylpyridine, and 0.6 M of
1,2-dimethyl-3-propylimidazolium iodide were dissolved in
acetonitrile to prepare a liquid electrolyte as an electrolytic
solution. Further, a Spacer-S "SURLYN" (trade name, manufactured by
DuPont), which has a shape matching to the size of the
photoconductor layer 42, was prepared.
[0600] Each of the light-receiving electrodes 40 manufactured as
above and the counter electrode 48 were arranged to face each other
through the spacer-S and thermally compressed, and then the liquid
electrolyte was filled from the inlet for the electrolytic solution
between the photoconductor layer 42 and the counter electrode 48,
thereby forming a charge transfer layer 47. The outer periphery and
the inlet for the electrolytic solution of thus manufactured cell
were sealed and cured using RESIN XNR-5516 (manufactured by Nagase
ChemteX Corporation), thereby producing each of dye-sensitized
solar cells (Sample Nos. 1 to 21).
[0601] The dye-sensitized solar cells with the respective Sample
Nos. produced as above encompass two kinds of dye-sensitized solar
cells, with ones using electrically neutral metal complex dyes (D-1
to D-21) and the others using metal complex dyes (D-1TBA to
D-21TBA) of TBA salts.
[0602] Furthermore, in the dye-sensitized solar cells with the
respective Sample Nos., the dye-sensitized solar cells using the
electrically neutral metal complex dyes encompasses two kinds of
the dye-sensitized solar cells produced using the light-receiving
electrode precursor [A] ("A" is attached to the Sample No.) and the
dye-sensitized solar cells produced using the light-receiving
electrode precursor [B] ("B" is attached to the Sample No.).
[0603] Similarly, the dye-sensitized solar cell using the metal
complex dye of the TBA salt encompasses two kinds of the
dye-sensitized solar cell produced using the light-receiving
electrode precursor [A] and the dye-sensitized solar cell produced
using the light-receiving electrode precursor [B].
[0604] For comparison, dye-sensitized solar cells (Sample Nos. c1
to c4) were produced in the same manner as for the production of
the dye-sensitized solar cells, except that each of the following
metal complex dyes (c-1) to (c-4) was used instead of the metal
complex dye synthesized in Example 1 in the production of the
dye-sensitized solar cell.
[0605] The metal complex dye (c-1) is the compound "Dye607"
described in JP2013-67773A. The metal complex dye (c-2) is an
electrically neutral metal complex dye of the compound "A-4"
described in JP2012-36237A. The metal complex dye (c-3) is the
compound "D-9" described in JP2013-229285A. The metal complex (c-4)
is an electrically neutral metal complex dye of "Example 12"
described in US2012/0247561A.
##STR00400## ##STR00401##
[0606] <Test of Photoelectric Conversion Efficiency>
[0607] Each of the produced dye-sensitized solar cells was used to
carry out a cell characteristic test. The cell characteristic test
was carried out by irradiating artificial sunlight of 1,000
W/m.sup.2 from a xenon lamp through an AM1.5 filter, using a solar
simulator (WXS-85H manufactured by WACOM). The current-voltage
characteristics were measured using an I-V tester to determine the
photoelectric conversion efficiency.
[0608] (Conversion Efficiency (A))
[0609] For each of the dye-sensitized solar cells (Sample Nos. 1A
to 21A and c1A to c4A) produced using the light-receiving electrode
precursors [A] in the dye-sensitized solar cells with the
respective Sample Nos., the photoelectric conversion efficiency
(referred to as conversion efficiency (A)) was measured as
described above. The measured conversion efficiency (A) was
evaluated. For the evaluation, the conversion efficiency (SA) of
the dye-sensitized solar cell (Sample Nos. c1A) produced by using
the light-receiving electrode precursor [A] was used as a
standard.
[0610] In the evaluation criteria of the conversion efficiency (A),
"A" and "B" are the acceptable levels in the present test, with "A"
being preferable.
[0611] (Evaluation Criteria for Conversion Efficiency (A))
[0612] The conversion efficiency (A) was evaluated as follows in
comparison with that of the conversion efficiency (S.sub.A).
[0613] A: More than 1.2 times
[0614] B: More than 1.1 times and 1.2 times or less
[0615] C: More than 1.0 time and 1.1 times or less
[0616] D: 1.0 time or less
[0617] (Conversion Efficiency (B))
[0618] For each of the dye-sensitized solar cells (Sample Nos. 1B
to 21B and c1B to c4B) produced using the light-receiving electrode
precursors [B] in the dye-sensitized solar cells with the
respective Sample Nos., the photoelectric conversion efficiency
(referred to as conversion efficiency (B)) was as described above.
The measured conversion efficiency (B) was evaluated. For the
evaluation, the conversion efficiency (S.sub.A) of the
dye-sensitized solar cell (Sample Nos. c1A) produced by using the
light-receiving electrode precursor [A] was used as a standard.
[0619] In the evaluation criteria of the conversion efficiency (B),
"A" and "B" are the acceptable levels in the present test, with "A"
being preferable.
[0620] (Evaluation Criteria for Conversion Efficiency (B))
[0621] The conversion efficiency (B) was evaluated as follows in
comparison with that of the conversion efficiency (S.sub.A).
[0622] A: More than 1.1 times
[0623] B: More than 1.0 time and 1.1 times or less
[0624] C: More than 0.9 times and 1.0 time or less
[0625] D: 0.9 times or less
[0626] <Evaluation of Durability>
[0627] The heat cycle test was carried out for evaluation on
durability (thermal deterioration), using each of the
dye-sensitized solar cells (Sample Nos. 1A to 21A and c1A to c4A)
produced using the light-receiving electrode precursors [A] in the
dye-sensitized solar cells with the respective Sample Nos.
[0628] Each of the dye-sensitized solar cells was alternately
introduced into a freezer at -10.degree. C. and a
constant-temperature tank at 50.degree. C. every 12 hours so as to
repeat cooling and heating (heat cycle test). The current was
measured for the dye-sensitized solar cells before the heat cycle
test and the dye-sensitized solar cell at 72 hours after the heat
cycle test, respectively. The value determined by dividing the
current value (short-circuit current density) determined from the
current-voltage characteristic measurement in the dye-sensitized
solar cell at 72 hours after the heat cycle test by the current
value (short-circuit current density) measured in the
dye-sensitized solar cells before the heat cycle test was taken as
a current holding ratio. By the current holding ratios thus
obtained, the durability was evaluated according to the following
criteria.
[0629] In the evaluation criteria for the durability, "A" and "B"
are the acceptable levels in the present test, with "A" being
preferable.
[0630] A: 0.9 times or more
[0631] B: Less than 0.9 times and 0.8 times or more
[0632] C: Less than 0.8 times and 0.7 times or more
[0633] D: Less than 0.7 times
TABLE-US-00002 TABLE 1 Sample Metal Conversion Conversion No.
complex dye efficiency (A) efficiency (B) Durability 1 D-1 A A A
D-1TBA A A B 2 D-2 A A A D-2TBA A A B 3 D-3 A A A D-3TBA A A B 4
D-4 A A A D-4TBA A A B 5 D-5 A A A D-5TBA A A B 6 D-6 A A A D-6TBA
A A B 7 D-7 A A A D-7TBA A A B 8 D-8 A A A D-8TBA A A B 9 D-9 A A A
D-9TBA A A B 10 D-10 A B A D-10TBA A B B 11 D-11 A B B D-11TBA A B
B 12 D-12 A A A D-12TBA A A B 13 D-13 A A A D-13TBA A A B 14 D-14 A
A A D-14TBA A A B 15 D-15 A A A D-15TBA A A B 16 D-16 A A A D-16TBA
A A B 17 D-17 A A A D-17TBA A A B 18 D-18 A A A D-18TBA A A B 19
D-19 A A A D-19TBA A A B 20 D-20 A B A D-20TBA A A B 21 D-21 A B A
D-21TBA A A B c1 c-1 D C C c2 c-2 C C D c3 c-3 D D B c4 c-4 D C
D
[0634] From the Results of Table 1, it can be Seen as Follows.
[0635] In any of Sample Nos. 1 to 21 (the present invention), metal
complex dyes (D-1 to D-21) having the tridentate ligand LA in which
the amino group-containing heteroarylene group was introduced into
the 4-position of the terminal pyridine ring of terpyridine were
used. In any of the photoelectric conversion elements and the
dye-sensitized solar cells of the present invention (Sample Nos. 1
to 21) in which these metal complex dyes (D-1 to D-21) were carried
on semiconductor fine particles, the conversion efficiency (A) and
the conversion efficiency (B) were both high, and the current
holding ratio was also high.
[0636] Furthermore, in the photoelectric conversion elements and
the dye-sensitized solar cells (Sample Nos. 1 to 10, and 12 to 21),
the metal complex dyes (D-1 to 10 and 12 to 21) having the
bidentate or tridentate ligand LD that coordinates with the
tridentate ligand LA and the anion were used. As a result, in any
case, the high conversion efficiency (A) and the conversion
efficiency (B) were held, and the current holding ratio became
higher.
[0637] In the photoelectric conversion elements and the
dye-sensitized solar cells (Sample Nos. 1 to 9 and 12 to 21), the
metal complex dyes (D-1 to 9, and 12 to 21) having the bidentate or
tridentate ligand LD that coordinates with the ligand LA into which
an amino group-containing heteroarylene group having a diarylamino
group was introduced, and the anion were used. All of these
photoelectric conversion element and dye-sensitized solar cells
(Sample Nos. 1 to 9 and 12 to 21) exhibited excellent photoelectric
conversion efficiency and high durability. Further, even when the
effect of the film thickness of the semiconductor layer was small
and the film thickness was reduced up to 6 .mu.m, the photoelectric
conversion efficiency was excellent and the durability was
high.
[0638] Among these, the metal complex dyes (D-1 to 9, and 12 to 19)
of the photoelectric conversion elements and the dye-sensitized
solar cells (Sample Nos. 1 to 9 and 12 to 19) have the ligand LA as
well as the ligand LD in which a pyridine ring has a group
represented by Formula (V.sup.U-1), an alkyl group, an alkoxy
group, or an amino group in which two groups bonded to a nitrogen
atom are not linked (a diarylamino group or an N-alkyl-N-arylamino
group) as a substituent. Such photoelectric conversion elements and
dye-sensitized solar cells (Sample Nos. 1 to 9 and 12 to 19) were
less affected by the film thickness of the semiconductor layer, and
exhibited more excellent photoelectric conversion efficiency even
when the film thickness was reduced up to 6 .mu.m.
[0639] In addition, the metal complex dyes of the present invention
provided the same results whether they were electrically neutral or
TBA salts.
[0640] Moreover, the metal complex dye of the present invention
could be suitably used as a sensitizing dye of the photoelectric
conversion element and the dye-sensitized solar cell of the present
invention. The dye solution of the present invention, containing
the metal complex dye of the present invention and a solvent, could
be suitably used for the preparation of semiconductor fine
particles carrying the metal complex dye of the present invention.
In addition, the terpyridine compound of the present invention was
suitable as a ligand of the metal complex dye of the present
invention, and in particular, an esterified product thereof was
suitable as a ligand precursor of the metal complex dye of the
present invention.
[0641] To the contrary, all of the comparative photoelectric
conversion elements and dye-sensitized solar cells (Sample Nos. c1
to c4), in which the metal complex dyes not having the ligand LA
was carried on the semiconductor fine particles did not reach the
acceptable levels in terms of the conversion efficiency and the
durability.
[0642] In the photoelectric conversion elements and the
dye-sensitized solar cells of Sample Nos. c1 and c4, the metal
complex dyes (c-1 and c-4) having a tridentate ligand in which a
substituent including an arylamino group was introduced to the
3-position of the terminal pyridine ring of terpyridine were used.
All of such photoelectric conversion elements and dye-sensitized
solar cells (Sample Nos. c1 and c4) did not reach the acceptable
levels in terms of the conversion efficiency (A), the conversion
efficiency (B), and the current holding ratio.
[0643] Although the present invention has been described with
reference to embodiments, it is not intended that the present
invention is not limited by any of the details of the description
unless otherwise specified, but should rather be construed broadly
within the spirit and scope of the present invention as set out in
the accompanying claims.
[0644] The present application claims the priority based on
JP2014-140078 filed on Jul. 7, 2014, and JP2015-113836 filed on
Jun. 4, 2015, the contents of which are incorporated by reference
into a part described herein.
EXPLANATION OF REFERENCES
[0645] 1, 41: ELECTRICALLY CONDUCTIVE SUPPORT [0646] 2, 42:
PHOTOCONDUCTOR LAYER [0647] 21: DYE [0648] 22: SEMICONDUCTOR FINE
PARTICLES [0649] 3, 47: CHARGE TRANSFER LAYER [0650] 4, 48: COUNTER
ELECTRODE [0651] 5, 40: LIGHT-RECEIVING ELECTRODE [0652] 6:
EXTERNAL CIRCUIT [0653] 10: PHOTOELECTRIC CONVERSION ELEMENT [0654]
100: SYSTEM IN WHICH PHOTOELECTRIC CONVERSION ELEMENT IS APPLIED TO
CELL USES [0655] M: OPERATING MEANS (FOR EXAMPLE, ELECTRIC MOTOR)
[0656] 20: DYE-SENSITIZED SOLAR CELL [0657] 43: TRANSPARENT
ELECTRICALLY-CONDUCTIVE FILM [0658] 44: SUBSTRATE [0659] 45:
SEMICONDUCTOR LAYER [0660] 46: LIGHT-SCATTERING LAYER [0661] S:
SPACER
* * * * *